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Comparative analysis of distinct genomic landscapes in young-onset gBRCA1/2 breast cancer.

Carriers of germline BRCA1/2 pathogenic variants (gBRCA1/2 PVs) have elevated young-onset breast cancer risk. To define the pretreatment genomic landscapes of young-onset gBRCA-associated breast cancer, we evaluated 136 treatment-naive tumors diagnosed before age 50 in the prospective POSH study and 66 noncarriers from The Cancer Genome Atlas. Using whole-exome sequencing, we analyzed somatic variation, allele-specific loss of heterozygosity (asLOH), homologous recombination deficiency (HRD), and single-base substitution (SBS) signatures. gBRCA1 and gBRCA2 breast cancers had high rates of asLOH but differed significantly in average HRD scores and median SBS composition of signatures SBS1 (aging-associated), SBS18 (ROS-associated), and SBS3 (HRD-associated). Compared with gBRCA2 tumors, gBRCA1 tumors with asLOH were significantly enriched for alterations in hallmark ROS, DNA repair, and epithelial-mesenchymal transition pathways. In ER-positive, HER2-negative tumors from gBRCA1/2 carriers compared with noncarriers, we found significant enrichment of RB1, TP53, FAT1, and MYC single-nucleotide variants, indels, and copy number variants associated with CDK4/6 inhibitor (CDK4/6i) resistance. Together, these findings demonstrate significant differences between gBRCA1- and gBRCA2-associated breast cancers, and preexisting CDK4/6i resistance mechanisms, supporting prospective trials comparing individualized therapy for gBRCA1 versus gBRCA2 carriers and comparing poly(ADP-ribose) polymerase inhibitors versus CDK4/6i for ER-positive gBRCA1/2-associated breast cancer.

Humans↗

A large AZFc deletion removes DAZ3/DAZ4 and nearby genes from men in Y haplogroup N.

Deletion of the entire AZFc locus on the human Y chromosome leads to male infertility. The functional roles of the individual gene families mapped to AZFc are, however, still poorly understood, since the analysis of the region is complicated by its repeated structure. We have therefore used single-nucleotide variants (SNVs) across approximately 3 Mb of the AZFc sequence to identify 17 AZFc haplotypes and have examined them for deletion of individual AZFc gene copies. We found five individuals who lacked SNVs from a large segment of DNA containing the DAZ3/DAZ4 and BPY2.2/BPY2.3 gene doublets in distal AZFc. Southern blot analyses showed that the lack of these SNVs was due to deletion of the underlying DNA segment. Typing 118 binary Y markers showed that all five individuals belonged to Y haplogroup N, and 15 of 15 independently ascertained men in haplogroup N carried a similar deletion. Haplogroup N is known to be common and widespread in Europe and Asia, and there is no indication of reduced fertility in men with this Y chromosome. We therefore conclude that a common variant of the human Y chromosome lacks the DAZ3/DAZ4 and BPY2.2/BPY2.3 doublets in distal AZFc and thus that these genes cannot be required for male fertility; the gene content of the AZFc locus is likely to be genetically redundant. Furthermore, the observed deletions cannot be derived from the GenBank reference sequence by a single recombination event; an origin by homologous recombination from such a sequence organization must be preceded by an inversion event. These data confirm the expectation that the human Y chromosome sequence and gene complement may differ substantially between individuals and more variations are to be expected in different Y chromosomal haplogroups.

Chromosome Mapping↗

High-accuracy SNV calling for bacterial isolates using deep learning with AccuSNV.

Accurate detection of mutations within bacterial species is critical for fundamental studies of microbial evolution, reconstruction of transmission events, and identification of antimicrobial resistance mutations. Although many tools have been developed to identify single-nucleotide variants (SNVs) from whole-genome sequencing, they often suffer from high false-positive rates owing to the complexity of bacterial genomes and the need for different filtering cutoffs across sample types and sequencing depths. As data sets increase in size, the manual filtering required for high accuracy presents a significant obstacle. Here, we present AccuSNV, a novel deep learning-based tool for high-precision and automated bacterial SNV calling. Unlike traditional methods that process one sample at a time, AccuSNV leverages a convolutional neural network (CNN) that integrates alignment information across multiple samples, enhancing precision through learned across-sample patterns. We evaluate AccuSNV against seven popular SNV-calling tools using simulated data from six bacterial species with varied sequencing depths, numbers of isolates, mutations, and divergence levels. To further validate its real-world utility, we test AccuSNV on multiple curated bacterial data sets containing reported SNVs. In both simulated and real-world scenarios, AccuSNV consistently achieves the best performance. Moreover, AccuSNV provides comprehensive user-friendly downstream analysis modules and outputs, including mutation annotation information, phylogenetic inference, d N/d S calculations, and optional manual filtering. Together with the automated deep learning-based calling, these features make AccuSNV broadly accessible to users with different levels of computational expertise.

Deep Learning↗

Large-scale simulation of coverage and error rate tradeoffs for cancer detection in cell-free DNA whole-genome sequencing.

MOTIVATION: Cell-free DNA (cfDNA) whole-genome sequencing (WGS) is a promising approach for detecting cancer recurrence. It enables cancer detection by identifying all tumor-derived cfDNA (ctDNA) molecules carrying somatic single nucleotide variants (sSNVs). While ideally, a sequencing platform should be highly accurate for reliable ctDNA detection, in reality, all sequencing platforms introduce sequencing errors that generate false positives indistinguishable from true SNVs. Understanding how sequencing parameters influence ctDNA detection sensitivity at low tumor fractions (TFs) in cfDNA samples is essential for guiding sequencing strategies in clinical contexts. To model cfDNA sequencing for tumor detection, which contains asymmetric noise and multiple interacting parameters, analytical modeling is intractable, motivating large-scale parallelized simulation. RESULTS: We developed a simulation framework to generate in silico cfDNA data across 10 cancer types. In total, 480 million cfDNA samples were simulated from tumor WGS profiles. Overall, the lowest detectable TF differs substantially between cancer types under identical sequencing conditions due to variations in mutational load. For cancers with high mutational load, 3× coverage with low-error techniques reliably detects TFs below 0.1%. In contrast, cancers with low mutational load require at least six-fold higher coverage to achieve comparable detection thresholds. Increasing sequencing quality scores from Q30 to Q55 at 30× coverage further enhances sensitivity, enabling detection of TFs as low as 1 × 10-5. This study provides a comprehensive framework for optimizing sequencing parameters, offering valuable guidance for tailoring future technology development for specific cancer types and clinical applications. AVAILABILITY AND IMPLEMENTATION: The code is publicly available at https://github.com/UMCUGenetics/cfdetect/tree/main.

Whole Genome Sequencing↗

AUTS2-related syndrome: Insights from a large European cohort.

PURPOSE: AUTS2-related syndrome is characterized by developmental delay, autism spectrum disorder, and intellectual disability. From alternative promoters, AUTS2 encodes 2 distinct long and short isoforms encoding a putative transcriptional activator. METHODS: Through a European collaborative study, we collected clinical and genotype data on the largest AUTS2-related syndrome cohort of 58 patients harboring genomic rearrangements or single-nucleotide variants (SNVs). RESULTS: Pathogenic SNVs were recurrently found in individuals from different countries, suggesting mutational hotspots. Independent of the underlying defect at the AUTS2 locus, we observed that autistic behavior, hyperactivity, learning difficulties, and speech delay are common features of AUTS2-related syndrome. Among patients with SNVs, individuals carrying pathogenic variants affecting both longer and shorter AUTS2 transcripts showed a recognizable phenotype with microcephaly, brachycephaly, microretrognathia, broad nasal base, and anteverted nares. Behavioral disorders were more common in patients with variants affecting only the longer isoform. Arthrogryposis and stiff movements were only observed in patients with SNVs. CONCLUSION: This study provides a comprehensive clinical characterization of AUTS2-related syndrome, reveals few genotype-phenotype correlations, and suggests that the disruption of the 2 distinct AUTS2 transcripts has a different impact on the clinical phenotype.

Humans↗

Enrichment of G-to-U Substitution in SARS-CoV-2 Functional Regions and Its Compensation via Concurrent Mutations.

We surveyed single nucleotide variant (SNV) patterns from 5 903 647 complete SARS-CoV-2 genomes. Among 10 012 SNVs, APOBEC-mediated C-to-U (C > U) deamination was the most prevalent, followed by G > U and other RNA editing-related substitutions including (A > G, U > C, G > A). However, C > U mutations were less frequent in functional regions, for example, S protein, intrinsic disordered regions, and nonsynonymous mutations, where G > U were over-represented. Notably, G-loss substitutions rarely appeared together. Instead, G-gain mutations tended to more frequently co-occur with others, with a marked preference in the S protein, suggesting a compensatory mechanism for G loss in G > U mutations. The temporal patterns revealed C > U frequency declined until late 2021 then resurged in early 2022. Conversely, G > U steadily decreased, with a pronounced drop in January 2022, coinciding with reduced COVID-19 severity. Vaccinated individuals exhibited a slightly but significantly higher C > U frequency and a notably lower G > U frequency compared to the unvaccinated group. Additionally, cancer patients had higher G > U frequency than general patients during the same period. Interestingly, none of the C > U SNVs were uniquely identified in 2724 environmental samples. These findings suggest novel functional roles of G > U in COVID-19 symptoms, potentially linked to oxidative stress and reactive oxygen species, while C > U remains the dominant substitution, likely driven by host immune-mediated RNA editing.

SARS-CoV-2↗

Hidradenitis Suppurativa and Smoking, Obesity, Psoriasis, Inflammatory Bowel Disease, and Systemic Sclerosis: Results From A 2-Sample Mendelian Randomization Study.

IMPORTANCE: Smoking and obesity are associated with risk of hidradenitis suppurativa, and both are considered important environmental risk factors. However, a causal relationship remains unproven. OBJECTIVE: To primarily investigate the relationship between body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) and smoking and HS, and secondarily to investigate potential relationships between 3 inflammatory diseases (psoriasis, inflammatory bowel disease [IBD], and systemic sclerosis [SSc]) and HS. DESIGN, SETTING, AND PARTICIPANTS: A mendelian randomization (MR) study conducted in 2024 on 5 exposure phenotypes (BMI, smoking, psoriasis, IBD, and SSc) on the outcome of phenotype HS was conducted. The MR analyses used large genetic White European cohorts from genome-wide association studies (GWAS) of each of the 6 phenotypes. Initial analyses were conducted May, 2024, and were updated in May, 2025. EXPOSURE: The 5 exposure phenotypes using predetermined genome-wide significant single-nucleotide variants as proxies for each particular exposure. RESULTS: The GWAS on HS included 4814 case patients and more than 1.2 million controls from Denmark, Iceland, Finland, the UK, and the US. The BMI GWAS involved 700&#x202f;000 individuals from the UK Biobank and GIANT consortium. Smoking data were obtained from 1.23 million participants in an international consortium. The psoriasis GWAS analyzed 39&#x202f;498 case patients and 286&#x202f;769 controls from White European populations and a DNA genetic testing company. The IBD GWAS meta-analysis included 38&#x202f;155 case patients and 48&#x202f;485 controls from the International Inflammatory Bowel Disease (IBD) Genetics Consortium. The SSc GWAS included 9095 case patients and 17&#x202f;584 controls from White European populations. Genetic correlations (rg) were found between HS and all exposure phenotypes except SSc (BMI: rg&#x2009;=&#x2009;0.36, P&#x2009;<&#x2009;.001; smoking: rg&#x2009;=&#x2009;0.33, P&#x2009;<&#x2009;.001; IBD: rg&#x2009;=&#x2009;0.25, P&#x2009;<&#x2009;.001; psoriasis: rg&#x2009;=&#x2009;0.34, P&#x2009;<&#x2009;.001; SSc: rg&#x2009;=&#x2009;0.33, P&#x2009;=&#x2009;.22). MR analyses supported an effect of BMI on HS (&#x3b2;&#x2009;=&#x2009;0.87; odds ratio [OR] per BMI unit, 1.20; 95% CI, 1.17-1.23; P&#x2009;<&#x2009;.001) without signs of pleiotropy (slope: &#x3b2;&#x2009;=&#x2009;0.91, P&#x2009;<&#x2009;.001, P for intercept&#x2009;=&#x2009;.76). Smoking showed a significant causal estimate (&#x3b2;&#x2009;=&#x2009;0.59, P&#x2009;<&#x2009;.001), but results became inconclusive in subsequent sensitivity analyses. Among IBD, psoriasis, and SSc, results supported a causal effect of IBD on HS (&#x3b2;&#x2009;=&#x2009;0.18, OR&#x2009;=&#x2009;1.20; 95% CI, 1.15-1.24; P&#x2009;<&#x2009;.001), without signs of pleiotropy. CONCLUSIONS AND RELEVANCE: These findings indicate causal effects of IBD and increased BMI on the risk of HS. This information may help physicians inform patients about disease risk contributed by modifiable lifestyle behaviors, which can be beneficial for planning lifestyle interventions.

Humans↗

Comparative dynamics of Japanese encephalitis virus adaptation in porcine macrophages and insect cells.

BACKGROUND: Japanese encephalitis virus (JEV) is a zoonotic mosquito-borne Orthoflavivirus that circulates primarily in birds and pigs. Previous observations of vector-free transmission between pigs indicates the possibility of single-host cycling in swine. Therefore, the aim of this work was to investigate the evolutionary pressure of single host cycling using a relevant primary cell culture model. METHODS: To investigate whether such single-host cycles affect viral infectivity, fitness and genomic adaptations, two strains and a reverse genetic cDNA-derived clone of JEV were serially passaged 12 times in primary porcine monocyte-derived macrophages (MDMs), in Aedes albopictus-derived C6/36 cells, and alternately between both cell types. Next-generation sequencing analysis was used to identify selected single nucleotide variants (SNVs) and haplotypes. Phenotype-to-genotype connections were confirmed using reverse genetics. RESULTS: For all viruses, serial passaging in MDMs - but not in C6/36 cells - led to a rapid increase in relative infectivity toward MDMs, accompanied by reduced plaque sizes in porcine endothelial cells. In contrast to C6/36 cells, MDM imposed a strong selective pressure, rapidly favoring selection of many SNVs and viral haplotypes. In addition, we identified a dominant selection of mutants with glutamic acid to lysine substitutions at positions 49 or 138 in the E protein, which explained the small plaque phenotype and caused viral sensitivity to heparin-mediated inhibition of attachment, indicating enhanced virus binding to glycosaminoglycans (GAG). The E138K mutant also explained the increased relative infectivity for MDM. CONCLUSION: This work demonstrates a high evolutionary pressure on JEV in MDM causing rapid selections of minor haplotypes. Furthermore, the efficient selection of E49K and E138K SNV, which were responsible for the phenotype, are likely caused by a selective pressure for GAG binding, observed in vitro with other mammalian cells.

Animals↗

Association of FOXC1 Duplications With Juvenile Open-Angle Glaucoma.

IMPORTANCE: While FOXC1 single-nucleotide variants and deletions are well-established causes of Axenfeld-Rieger syndrome, few FOXC1 duplications have been reported. This study investigated families with duplications encompassing the FOXC1 gene to refine the associated phenotypic spectrum and contribution to glaucoma. OBJECTIVE: To investigate the prevalence and phenotype of FOXC1 duplications in 2 large glaucoma registries. DESIGN, SETTING, AND PARTICIPANTS: This retrospective observational genetic cohort study included participants recruited from the Australian & New Zealand Registry of Advanced Glaucoma (ANZRAG) and the Massachusetts Eye and Ear (MEE) cohort from 2008 through 2025. Participants with glaucoma, and available relatives, underwent genomic testing to identify duplications encompassing FOXC1 using exome sequencing and genotyping arrays (ANZRAG) or whole-genome sequencing (MEE). Data analyses were conducted from 2022 through 2025. MAIN OUTCOMES AND MEASURES: Prevalence of FOXC1 duplications, age at glaucoma onset, and phenotype, including ocular and systemic features. RESULTS: Twenty individuals from 10 families (50% female and 50% male; 70% self-described as broadly European [Australian/British, British, English/German, English/Polish, European, or Scottish], 25% as Asian [Chinese or Filipino], and 5% as Latin American [Salvadoran]) were identified with FOXC1 duplications. All genetically tested individuals were diagnosed with glaucoma, demonstrating high penetrance. Seventeen individuals were referred with juvenile open-angle glaucoma (JOAG), 1 with primary open-angle glaucoma, 1 with primary congenital glaucoma, and 1 with anterior segment dysgenesis. The diagnosis of 4 individuals from 1 family with ectropion uveae was revised to anterior segment dysgenesis. Systemic features were reported for 2 participants (10.5%), including subtle dental findings and mild facial dysmorphism. Duplications encompassing FOXC1 were among the most common monogenic contributors to JOAG. In the ANZRAG group, they accounted for 13.5% (95% CI, 6.7%-25.3%) of JOAG probands with a genetic diagnosis, second to MYOC (53.8%; 95% CI, 40.5%-66.7%). In the MEE group, FOXC1 duplications accounted for 9.5% (95% CI, 2.7%-28.9%) of JOAG probands with a genetic diagnosis. CONCLUSIONS AND RELEVANCE: These findings suggest FOXC1 duplications are an underrecognized, highly penetrant, but variably expressive, genetic variation associated with JOAG. Findings for the relatively modest number of individuals in the retrospective study were associated with wide confidence intervals. This limitation is often inherent to studies of JOAG, a rare condition for which individual genetic variants account for only a subset of cases. Despite this, the findings highlight the genetic heterogeneity of JOAG and support the potential importance of considering routine genetic copy-number variant analysis for individuals with JOAG.

Humans↗

Placental Site Trophoblastic Tumor Acquires Immune Functions by Incorporating Host Maternal Genes.

Although it was proposed that cell fusion of cancer cells with leukocytes creates mobile hybrids with a metastatic phenotype, it has been difficult to genetically confirm cell fusion events in human cancer in vivo. Here, we experienced 4 cases of placental site trophoblastic tumor (PSTT) that produced immunoglobulin (Ig). Three cases showed recurrence and responded well to pembrolizumab therapy. Among them, we could analyze temporal changes in the genetic profiles on one case of daughter-derived PSTT, which relapsed after pembrolizumab therapy. In this case, we found that PSTT incorporated the exogenous genes from host maternal cells. The rearrangement patterns of Ig genes and protein expressions sequentially increased. By analyzing single-nucleotide variants, PSTT incorporated daughter-non-inherited maternal alleles (DNIMA), including the Ig lambda and HLA-DQA2 loci. Protein expressions of TLR10 and SIGLEC10 increased during tumor progression concomitantly with DNIMA incorporation. DNIMA mapping indicates the incorporation of exogenous maternal genes was widely distributed through the whole chromosomes, suggesting the involvement of cell fusion in gene transfer mechanisms. These findings indicate that PSTT sequentially incorporated exogenous genes from maternal cells to express immune-related molecules and suggest that cancer cells acquired B cell-related functions, including Ig production by cell fusion with host immune cells.

Humans↗

Investigations of the genomic region that contains the clf1 mutation, a causal gene in multifactorial cleft lip and palate in mice.

BACKGROUND: Human nonsyndromic cleft lip and palate, CL(P), is genetically complex, with one contributing gene on chromosome 17q. A potentially homologous gene, clf1 on distal chromosome 11, is part of the digenic cause of the 10-30% CL(P) in the A/WySn mouse strain. Here we report our progress toward identifying the clf1 mutation. METHODS: Transcription from all of the known and predicted genes in the 1.5-Mb candidate region was examined in A/WySn and control (AXB-4/Pgn) ED10-11 embryo heads. The marker haplotype for 28 inbred strains across the clf1 region was obtained. The entire transcripts of Wnt9b and Wnt3 in A/WySn were sequenced. Using long PCR, the genomic region from Wnt3 throughWnt9b was screened in A/WySn for an inserted retrotransposon. RESULTS: Gosr2, Wnt9b, Wnt3, Nsf, Arf2, Crhr1, Mapt, Cdc27, Myl4, Itgb3, chr11_20.152, chr11_20.154, chr11_20.155, and chr11_20.156 are expressed in ED10-11 heads. None is absent or detectably reduced in A/WySn. The ancestral pre-clf1 mutation haplotype was found in CBA/J mice. By a test-cross, CBA/J was confirmed to lack the clf1 mutation. Three single-nucleotide variants in A/WySn (vs. C57BL/6J) were found in each of the 3' untranslated regions (3'UTRs) of Wnt3 and of Wnt9b, respectively; their presence in CBA/J shows that none are the clf1 mutation. An inserted intracisternal A particle (IAP) retrotransposon located 6.6 kb from the 3' end of Wnt9b was found in A/WySn and in all clf1 strains tested. This IAP is absent in C57BL/6J and CBA/J. CONCLUSIONS: The clf1 mutation is a genomic alteration present in A/WySn and absent in the ancestral chromosomal segment in CBA/J. The IAP retrotransposon insertion near Wnt9b in A/WySn fits this criterion; we predict that interference with Wnt9b function by this IAP is the clf1 mutation.

Animals↗

A novel approach for the analysis of DAZ gene copy number in severely idiopathic infertile men.

The deleted-in-azoospermia (DAZ) gene family constitutes the major candidate for the AZFc (azoospermia factor c) phenotype of male infertility, being deleted in about 10% of azoospermic and severely oligozoospermic subjects. Four DAZ genes are arranged in two clusters in AZFc, and standard analysis by PCR cannot distinguish among the different copies. Therefore only deletions of the entire gene cluster can be identified. We developed a PCR amplification-restriction digestion assay able to distinguish from DAZ genes for single nucleotide variants. Then we applied this approach to screen a group of idiopathic infertile men in which the DAZ genes presence was previously assessed by standard PCR analysis. Two patients out of 25 showed deletion of two copies of DAZ (DAZI and 2), suggesting that this mutation was actually the cause of spermatogenic damage. This preliminary screening demonstrates that deletions of copies of DAZ genes may be often found in severely infertile men and it strengthens the role of this gene family in spermatogenesis. Furthermore, this simple method, being able to distinguish among the different DAZ copies, could be used to screen a larger number of patients and to perform a more accurate diagnosis.

Deleted in Azoospermia 1 Protein↗

Characterization of the dog Agouti gene and a nonagoutimutation in German Shepherd Dogs.

The interaction between two genes, Agouti and Melanocortin-1 receptor ( Mc1r), produces diverse pigment patterns in mammals by regulating the type, amount, and distribution pattern of the two pigment types found in mammalian hair: eumelanin (brown/black) and pheomelanin (yellow/red). In domestic dogs ( Canis familiaris), there is a tremendous variation in coat color patterns between and within breeds; however, previous studies suggest that the molecular genetics of pigment-type switching in dogs may differ from that of other mammals. Here we report the identification and characterization of the Agouti gene from domestic dogs, predicted to encode a 131-amino-acid secreted protein 98% identical to the fox homolog, and which maps to chromosome CFA24 in a region of conserved linkage. Comparative analysis of the Doberman Pinscher Agouti cDNA, the fox cDNA, and 180 kb of Doberman Pinscher genomic DNA suggests that, as with laboratory mice, different pigment-type-switching patterns in the canine family are controlled by alternative usage of different promoters and untranslated first exons. A small survey of Labrador Retrievers, Greyhounds, Australian Shepherds, and German Shepherd Dogs did not uncover any polymorphisms, but we identified a single nucleotide variant in black German Shepherd Dogs predicted to cause an Arg-to-Cys substitution at codon 96, which is likely to account for recessive inheritance of a uniform black coat.

Agouti Signaling Protein↗

Lock and roll: single-molecule genotyping in situ using padlock probes and rolling-circle amplification.

In this review I will describe the development of a technique that enables genotyping of individual DNA molecules in the context of morphologically preserved fixed cells, from the fundamental concept published in 1994 to the present status. The review describes enzyme-assisted histochemistry approaches to achieve highly specific molecular identification reactions coupled to efficient signal amplification. The primary molecular identification is accomplished through circularization of oligonucleotide probes, called padlock probes. The circularization reaction is catalyzed by a DNA ligase, which provides robust distinction between single-nucleotide variants under standard reaction conditions. To generate a detectable signal from individual circularized probe molecules, a DNA polymerase is added that replicates probe circles, generating a long tandem-repeated DNA product, easily visualized using a standard epi-fluorescence microscope. Individual signals are recorded as bright dots, providing digital information about the abundance of specific sequences and opportunities for simultaneous detection of several targets using spectral multiplexing. The importance of strictly target-dependent signal amplification will be discussed.

Animals↗

A mutation in PCSK9 causing autosomal-dominant hypercholesterolemia in a Utah pedigree.

Familial hypercholesterolemia results from mutations in the low-density lipoprotein (LDL) receptor or apolipoprotein B genes. We have previously reported the identification of a Utah autosomal-dominant hypercholesterolemia pedigree (kindred 1173) that did not show linkage to either of these loci (Hunt et al. 2000). Expansion of the pedigree and increased marker density within the region of interest have resulted in a multipoint LOD score of 9.6 and enabled us to decrease the size of the linked region to approximately 7.5 Mbp. In addition, we were able to identify additional families sharing the same microsatellite haplotype. While all haplotype carriers in kindred 1173 (K1173) are affected, the haplotype carriers within the newly identified families are unaffected, suggesting that the causal mutation in K1173 had occurred after divergence of these pedigrees from a common ancestor. Mutation screening of genes in the region identified a single nucleotide variant (G-->T) present on the K1173 haplotype that was not present on the same haplotype in the other kindreds. This variant results in a D374Y missense change in the gene PCSK9.

Female↗

Non-HLA Genetics and Application to Living Donor Candidates.

PURPOSE OF REVIEW: This review examines the expanding role of non-human leukocyte antigen (non-HLA) genetic factors in kidney transplantation, with a particular focus on their implications for living donor evaluation and outcomes. It emphasizes the potential of genetic testing to improve risk stratification beyond conventional HLA matching, especially for donor candidates with a family history of hereditary kidney disease. RECENT FINDINGS: Non-HLA genetic mismatches, including single nucleotide variants affecting minor histocompatibility antigens, can drive alloimmune responses, leading to graft rejection and failure even in HLA-matched transplants. The presence of non-HLA antibodies further contributes to adverse immunological outcomes. Genetic testing in related living donors can uncover monogenic kidney diseases, enabling early identification of at-risk individuals and enhancing donor safety. While polygenic risk scores and gene panels show promise in predicting complications and guiding post-transplant care, most genome-wide association studies have focused on recipients. There remains a significant gap in understanding how donor-specific genetic factors influence post-donation kidney function and long-term health outcomes. SUMMARY: The integration of non-HLA genetic testing into living donor evaluation supports a precision medicine approach to kidney transplantation, offering improved risk assessment and donor-recipient matching. As the field advances, longitudinal studies and robust data collection, particularly around donor genetics, are essential to optimize transplant outcomes, inform clinical decision-making, and uphold ethical standards in donor care.

genetics↗

Polygenic risk score for early identification of coronary artery disease in a real-world clinical setting within the Latvian patient population.

STUDY OBJECTIVE: Polygenic risk scores (PRS) are increasingly recognized for their potential to improve coronary artery disease (CAD) prediction beyond traditional clinical models. This study evaluated the utility of genome-wide association study (GWAS) - derived PRS and pathway-specific PRS (PS-PRS) in the Latvian population, aiming to assess their association with CAD and compare their predictive performance with conventional risk factors. DESIGN PARTICIPANTS AND MAIN OUTCOME MEASURES: The study included 90 early-onset CAD patients and 43 controls with no evidence of atherosclerotic lesions on coronary angiography, with next-generation sequencing performed. PRS was calculated using 192 single nucleotide variants identified from the CARDIoGRAMplusC4D GWAS meta-analysis. The predictive accuracy of PRS, PS-PRS, clinical risk factors, and their combinations was analyzed via ROC curves. RESULTS: The average age was 48.7&#xa0;years in CAD patients and 49.8 in controls. CAD patients showed significantly higher PRS (mean 0.31) compared to controls (mean&#xa0;-&#xa0;0.65; p&#xa0;<&#xa0;0.0001). PRS alone had moderate discriminatory power (AUC&#xa0;=&#xa0;0.773), slightly lower than LDL cholesterol (AUC&#xa0;=&#xa0;0.775) and total cholesterol (AUC&#xa0;=&#xa0;0.821). Combining clinical risk factors improved prediction (AUC&#xa0;=&#xa0;0.872), with the highest accuracy when PRS was integrated with all clinical factors (AUC&#xa0;=&#xa0;0.933). The PRS distributions were significantly elevated in early-onset CAD patients across the angiogenesis/tissue repair pathway (p&#xa0;=&#xa0;0.00038), inflammation pathway (p&#xa0;=&#xa0;0.043), vascular remodelling pathway (p&#xa0;=&#xa0;0.0116), and pathway of genes with unknown function in atherosclerosis (p&#xa0;=&#xa0;0.0035), but overall PRS demonstrated superior discrimination compared to pathway-specific PRS. CONCLUSIONS: Incorporating PRS enhances early-onset CAD risk prediction. Pathway specific PRS had lower discriminative ability than the overall PRS.

Atherosclerosis↗

Polygenic Risk Scores Predicting Estimated GFR Validated With Iohexol Clearance.

INTRODUCTION: Genome-wide association studies (GWAS) have identified hundreds of single nucleotide variants (SNVs) associated with estimated glomerular filtration rate (eGFR). eGFR has been used as a proxy phenotype because of the complexity and cost of measured GFR (mGFR) in large studies. Because eGFR is influenced by non-GFR factors, these GWAS results may be biased compared with a hypothetical study using mGFR. We aimed to investigate this by comparing aggregate measures of genetic effects on mGFR and eGFR. METHODS: We studied 1492 persons from the Renal Iohexol Clearance Survey (RENIS) cohort, a representative sample of the general population in Northern Norway without preexisting cardiovascular disease, kidney disease, or diabetes. We measured iohexol-clearance, and genotyping was performed with a microarray chip enriched for GFR-related SNVs. We compared the performance of 3 published polygenic risk scores (PGS) developed for creatinine-based eGFR (eGFRcr), narrow-sense heritability (h2) and the mean effect of SNVs on mGFR, eGFRcr, cystatin C-based eGFR (eGFRcys) and eGFRcr-cys. RESULTS: The performance of the PGS differed for mGFR and the 3 eGFRs, with best performance for prediction of eGFRcr (P < 0.05). However, when the beta coefficients of the SNVs in the 3 PGS were estimated in the RENIS-cohort, their magnitude was 11% to 46% greater for mGFR than for the 3 eGFR methods in 8 of 9 comparisons (P < 0.05). mGFR had higher h2 (0.47) than eGFRcr (0.21), eGFRcys (0.37), and eGFRcr-cys (0.42). CONCLUSIONS: SNVs with non-GFR effects on creatinine and cystatin-C influence GWAS results. The results of GWAS using eGFR should be validated using experimental and other more precise methods.

chronic kidney disease↗