PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “genotype II”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed1977

Influence of genetic factors on the fertilization of mouse ova in vitro.

In-vitro fertilization was studied in F1 hybrids, 4 inbred and outbred strains of mice. Experiments were performed with intact ova (Series I) and denuded ova (Series II). In Series I the highest percentages of fertilization were obtained with gametes of F1 hybrids (86.7%) and of the CBA strain (87.5%). The KP, KE, and particularly the C57 strains, which in vivo give less than 100% fertilization, also gave low indices in vitro (42.9, 26.0 and 8.6% respectively). Testing gametes of these inbred strains with F1 gametes showed that spermatozoa and ova are responsible for the low percentages of fertilization. The rate of fertilization was mainly dependent on the genotype of the spermatozoon. In Series II, high percentages of fertilization (97-100%) were regularly obtained in all groups, indicating that differences between strains pertained mainly to binding of spermatozoa with the zona pellucida. The incidence of polyspermy, which did not exceed 5% in Series I and reached 58% in Series II, was dependent on the genotype of both gametes.

Animals↗
PubMed1976

Hybrid-versus-parental strain reaction. II. Comparative mortality in parental strain mice of different H-2 genotypes.

Lethally irradiated perental strain mice were inoculated with marrow from reciprocal hybrid donors. Hybrid cells could recognize the quantitatively greater antigenicity of parental strain recipients. The severity of the hybrid-versus-parental strain and parental strain-versus-hybrid reactions was compared. There was a significantly less severe reaction when DBA/2 mice were inoculated with (DBA/2female X C57BLmale)F1 arrow than with (C57BL X DBA/2)F1 marrow, which indicated a maternal influence on antigen recognition. The reaction of (DBA/2 X C57BL)F1 against DBA/2 recipients was significantly less severe than the DBA/2 reaction against (DBA/2 X C57BL)F1 recipients. All reactions involving C57BL were equally severe and more lethal than those involving DBA/2 mice. The strength of these reactions was a function of the relative tissue antigenicity and responsiveness of the parental strains of the hybrid cross. Both the expression of tissue antigens and the ability to recognize and respons to them are influenced by the maternal strain of the hybrid cross.

Animals↗
PubMed1976

Genetic evidence for a product of the Fv-1 locus that transfers resistance to mouse leukemia viruses.

Extracts of mouse cells have been shown to transfer to N- or B-trophic host range types of mouse leukemia viruses. The genetic specificity of the inhibition was tested in two ways: (i) by correlating the Fv-1 genotype of a number of mouse strains with the restriction-transferring activity of extracts of the respective embryo cell cultures, and (ii) by correlating the Fv-1 genotype of BLC3F2 (C57BL/6 female [Fv-1bb] by C3H male [Fv-1nn] parental strains) mouse embryos, which segregate the Fv-1 alleles in a 12:1 ratio, with the inhibitor activity of extracts of the cells from each embryo. Five independent matings, totaling 45 individual embryos, were tested. Each embryo was cultured, and the Fv-1 genotype was determined independently by titration of N- and B-tropic viruses; the extracts of replicate secondary cultures were tested for their effect on infection of permissive cells by N- and B-tropic viruses. The specific-restriction-transferring activity of the embryos was found to segregate with the appropriate Fv-1 genotype. These res-lts confirm the suggestion that the inhibitor of the leukemia virus host range types in the cellular extracts is a product of the Fv-1 locus.

AKR murine leukemia virus↗
PubMed2026

Management and Consequences of Genotype-Positive Familial Hypercholesterolemia.

IMPORTANCE: Familial hypercholesterolemia (FH) is a common genetic condition that causes hypercholesterolemia and increased risk for premature atherosclerotic cardiovascular disease (ASCVD). The prevalence, management, and consequences of genetically confirmed FH across the US are poorly understood. OBJECTIVE: To identify genotype-positive FH in a national US cohort and describe its prevalence, consequences, and lipid-lowering management. DESIGN, SETTING, AND PARTICIPANTS: In the All of Us (AoU) cohort study, whole-genome sequencing and phenotypic data from US adult participants enrolled between May 2018 and July 2022 were analyzed to identify and study genotype-positive FH. Data were analyzed between May 2024 and May 2025. EXPOSURE: FH variants (pathogenic or likely pathogenic) in LDLR, APOB, and PCSK9 genes were manually classified with standard criteria. MAIN OUTCOMES AND MEASURES: The primary outcomes were demographic characteristics, lipid measurements, ASCVD, and prevalence of FH and noncarriers in AoU. Lipid management was then characterized among individuals with FH through lipid-lowering therapy (LLT) documentation and guideline-based low-density lipoprotein cholesterol (LDL-C) targets. RESULTS: A total of 245&#x202f;388 participants were included, with mean (SD) age of 56.5 (16.9) years and 145&#x202f;563 female participants (59.3%). Genotype-positive FH was identified in 865 participants (prevalence, 0.35%; 95% CI, 0.33%-0.38%; 1 in 287 participants). Among individuals with genotype-positive FH, 349 (40%) were prescribed statins, and 332 (38.4%) had LDL-C measured. Coronary artery disease, peripheral artery disease, and transient ischemic attack or stroke were significantly more common in genotype-positive FH carriers compared to noncarriers (coronary artery disease: odds ratio [OR], 2.91; 95% CI, 2.34-3.58; peripheral artery disease: OR, 1.51; 95% CI, 1.16-1.96; and transient ischemic attack or stroke: OR, 1.54; 95% CI, 1.11-2.09). Only 30.1% of participants positive for FH variants had LDL-C less than 100 mg/dL at their most recent result compared to 48.2% of noncarriers (P&#x2009;<&#x2009;.001). Of the total participants with ASCVD and LLT prescription, significantly fewer individuals with FH met the secondary prevention LDL-C target (<70 mg/dL; 19.33% vs 43.12%; P&#x2009;<&#x2009;.001) compared to noncarriers. CONCLUSIONS AND RELEVANCE: This cohort study finds a prevalence of genotype-positive FH in All of Us participants of 0.35% (95% CI, 0.33%-0.38%), with state-level variation. A minority of individuals with genotype-positive FH met guideline-recommended LDL-C targets and had increased rates of ASCVD.

Humans↗
PubMed1979

Anti-tissue antibodies and immunoglobulin levels in relation to HLA and other markers in Icelandic families.

Studies of 521 sera from the Icelandic cousin marriage project were made to assess the incidence of various anti-tissue antibodies and the levels of immunoglobulins, as these were considered to be useful markers of the humoral immune response. Comparisons were made between these parameters and the HLA-A and B antigens, the blood groups, the immunoglobulin allotypes (Gm, Km and Am), the properdin factor (Bf), and other markers. These investigations offered another approach to the study of the sites of action of immune response genes in man. Because the immune response may be expected to differ for each individual and depend at least in part, on the degree of exposure to different antigens, no absolute correlation was expected. There was, however, a marked association between certain IgG anti-tissue antibodies and HLA antigens. This was most marked for HLA-A10, B18 and b27, but not for HLA-A1 or B8. The comparison of immunoglobulin levels with HLA antigens, was less striking, although HLA-A2 appeared to be associated with low levels of IgE. There were also some associations between immunoglobulin levels and ABO blood groups.

Aged↗
PubMed1978

Genetic separation of high- and low-affinity transport systems for branched-chain amino acids in Escherichia coli K-12.

The Escherichia coli K-12 mutant strain AE4107 (livH::Mu) is defective in the high-affinity binding protein-mediated uptake system for L-leucine, L-valine, and L-isoleucine (LIV-I). We have used this strain to produce mutations in the residual LIV-II membrane-bound branched-chain amino acid uptake system. Mutants selected for their inability to utilize exogenous L-leucine were found to be defective in the LIV-II system and fell into two classes. One class, represented by strain AE410709 (livP9), showed a complete loss of saturable uptake for L-leucine, L-valine, and L-isoleucine up to 50 muM, and a second class, represented by strain AE4017012 (liv-12), showed a residual component of saturable leucine uptake with increased Km. These mutations, livP9 and liv-12, were closely linked and mapped in the 74 to 78 min region of the E. coli genetic map. Strains constructed so that they lacked both LIV-I and LIV-II transport systems excreted leucine. Strains of the genotype livH+ livP were found to have normal high-affinity binding protein-mediated transport (LIV-I and leucine specific), whereas the low-affinity (LIV-II) transport was completely missing. We concluded from these studies that the high-affinity binding protein-mediated transport systems (LIV-I and leucine specific) can operate independently of the membrane-bound LIV-II system.

Biological Transport, Active↗
PubMed1978

Mucosal iron binding proteins in sex-linked anemia and microcytic anemia of the mouse.

The duodenal mucosa of genotypically normal iron replete and iron deficient mice and mice with sex-linked (sla) and microcytic anemias (mk) was examined for the presence of iron-binding proteins. Following continuous, 15 or 120 minute, in vivo intraenteric exposure of a closed duodenal loop to 59Fe, a high speed supernatant of homogenized mucosal tissue was chromatographed on G-200 Sephadex. Two major peaks of 59Fe activity were observed. The molecular weight, and immunological properties of peak I were similar to ferritin whilst those of peak II were similar to transferrin. The distribution of 59Fe between peaks I and II in mk/mk animals was similar to that in genotypically normal iron deficient animals indicating that the intramucosal mechanisms for iron transport were reacting appropriately to the iron deficient state of mice with microcytic anemia. In contrast, the distribution of 59Fe between peaks I and II in sla/Y animals was the reverse of that found in genotypically normal iron deficient animals suggesting the possibility of an intramucosal iron binding protein defect in sex-linked anemia.

Anemia, Hypochromic↗
PubMed2026

[Empirical Classification of Tri-Allelic Genotype Cases and Parentage Index Calculation].

OBJECTIVES: To standardize the calculation method of the parentage index (PI) for short tandem repeat (STR) tri-allelic genotypes, thereby ensuring the accuracy and reliability of parentage tes&#x2011; ting conclusions. METHODS: A systematic analysis of 160 real cases was conducted. A classification system was constructed based on the occurrence mechanisms and inheritance patterns of STR tri-alleles, and the PI calculation method was optimized by integrating previous research findings with empirical data. RESULTS: A mechanism-based classification system for STR tri-allelic genotypes was established, comprising Type I (2 subtypes), Type II (6 subtypes), and the trisomic type (2 subtypes). On this basis, a standardized PI calculation method covering all categories of STR tri-allelic genotypes was developed. CONCLUSIONS: This study provides methodological guidance for the scientific and standardized calculation of PI for STR tri-allelic genotypes and offers an important reference for the formulation and refinement of relevant industry standards.

Humans↗
PubMed1976

The correlation between the protein composition of cytoplasmic membranes and the formation of nitrate reductase A, chlorate reductase C and tetrathionate reductase in Proteus mirabilis wild type and some cholate resistant mutants.

Three genotypically different chlorate resistant mutants, chl I, chl II and chl III, appeared to lack completely nitrate reductase A, chlorate reductase C and tetrathionate reductase activity. Fumarate reductase is only partially affected in chl I and chl III and unaffected in chl II. Formate dehydrogenase is only partially diminished in chl II, hydrogenase is diminished in chl I and chl II and completely absent in chl III. Subunits of nitrate reductase A, chlorate reductase C and tetrathionate reductase have been identified in protein profiles of purified cytoplasmic membranes from the wild type and the three mutant strains, grown under various conditions. Only the presence and absence of the largest subunits of these enzymes appeared to be correlated with their repression and derepression in the wild type membranes. On the cytoplasmic membranes of the chl I and chl III mutants these subunits lack for the greater part. In the chl II mutant, however, these subunits are inserted in the membrane all together after anaerobic growth with or without nitrate. A model for the repression/derepression mechanism for the reductases has been proposed. It includes repression by cytochrome b components, whereas the redox-state of the nitrate reductase A molecule itself is also involved in its derepression under anaerobic conditions.

Anaerobiosis↗
PubMed2026

Pedigree-assisted genotype imputation enables cost-effective genomic prediction in Penaeus vannamei.

Genomic selection in Penaeus vannamei has long been constrained by the high cost of dense genotyping. To address this limitation, we evaluated genotype imputation from a low-density 1&#xa0;K panel to a medium-density 55&#xa0;K panel of the "Yellow Sea Array No. 1" and examined its impact on genomic prediction for harvest body weight in P. vannamei. A four-generation pedigree including 30 great-grandparents, 39 grandparents, 100 parents, and 608 offspring was genotyped using the 55&#xa0;K panel. A two-step experimental design was implemented to (i) assess the performance of different imputation algorithms under reference population scenarios with varying proportions of siblings, and (ii) compare six alternative reference population structures incorporating parents, ancestors, and siblings. Genotype imputation using the pedigree-based method FImpute v3.0 consistently achieved higher accuracy than the population-based method Beagle v5.5. Using this pedigree-assisted approach, imputation accuracy increased from 0.73 when only parental genotypes were used to 0.84 with the inclusion of 10% siblings, and subsequently plateaued at 0.87-0.90 when sibling representation reached 20%. Across the six reference population structures, imputation accuracy was primarily driven by the availability of parental genotypes, ranging from 0.50 to 0.56 in the absence of parents to 0.88-0.89 when both parents and ancestral generations were included. Accuracy remained high when both parents were available (0.84-0.87 with siblings; 0.73 without siblings) but declined substantially when only one parent was genotyped (0.65-0.68). Imputation accuracy was positively associated with both minor allele frequency (MAF) and linkage disequilibrium (max r2LD), with LD exerting the stronger influence. Heritability estimates derived from imputed 55&#xa0;K genotypes were highly consistent with those obtained from the original 55&#xa0;K data (0.39&#x2009;&#xb1;&#x2009;0.14 vs. 0.41&#x2009;&#xb1;&#x2009;0.14), indicating that genotype imputation did not compromise variance component estimation. In predictive ability analyses, pedigree-based BLUP (PBLUP) achieved higher predictive ability than genomic BLUP (GBLUP) based on the 1&#xa0;K panel, with predictive abilities of 0.42-0.44 for PBLUP compared with 0.34-0.35 for GBLUP. Using imputed genotypes for genomic prediction further improved predictive ability relative to the true 1&#xa0;K panel, yielding values ranging from 0.35 to 0.47. Notably, when parental genotypes were included in the reference population, GBLUP based on imputed genotypes surpassed the predictive ability of PBLUP and approached that achieved with the original 55&#xa0;K genotypes (0.45-0.47). Collectively, these results provide the first empirical evidence that low- to medium-density genotype imputation, combined with pedigree information, can effectively support genomic prediction in P. vannamei. This study establishes a cost-efficient and scalable framework for implementing genomic selection in P. vannamei and provides a practical reference for the application of genomic selection in other aquaculture species with constrained breeding budgets.

Animals↗
PubMed1977

[Genetic structure of an isolated native population group of northern Sibiria, the Nganasani (Tavgi) of the Taimyr. II. An analysis of intrapopulation variability].

Chi-square contingency table analysis of phenotypic (genotypic) and gene frequencies of erythrocyte and blood serum groups and enzymes in a group of reindeer hunter and fishermen revealed heterogeneity within the population studied. Four out of twelve loci which have been compared were found to be involved in the process of differentiation into two local subgroups (subpopulations). No statistical differences have been observed between samples arbitrarily representing three generations. The data obtained support the hypothesis that the whole population still preserves the state of the stability. Traditional migration from adjacent populations close to nganasans by language and culture has made an important contribution into heterogeneity found in nganasans.

Adult↗
PubMed2024

Genetics of constant and severe pain in the NAPS2 cohort of recurrent acute and chronic pancreatitis patients.

Recurrent acute and chronic pancreatitis (RAP, CP) are complex, progressive inflammatory diseases with variable pain experiences impacting patient function and quality of life. The genetic variants and pain pathways in patients contributing to most severe pain experiences are unknown. We used previously genotyped individuals with RAP/CP from the North American Pancreatitis Study II (NAPS2) of European Ancestry for nested genome-wide associated study (GWAS) for pain-severity, chronicity, or both. Lead variants from GWAS were determined using FUMA. Loci with p<1e-5 were identified for post-hoc candidate identification. Transcriptome-wide association studies (TWAS) identified loci in cis and trans to the lead variants. Serum from phenotyped individuals with CP from the PROspective Evaluation of Chronic Pancreatitis for EpidEmiologic and Translational StuDies (PROCEED) was assessed for BDNF levels using Meso Scale Discovery Immunoassay. We identified four pain systems defined by candidate genes: 1) Pancreas-associated injury/stress mitigation genes include: REG gene cluster, CTRC, NEURL3 and HSF22. 2) Neural development and axon guidance tracing genes include: SNPO, RGMA, MAML1 and DOK6 (part of the RET complex). 3) Genes linked to psychiatric stress disorders include TMEM65, RBFOX1, and ZNF385D. 4) Genes in the dorsal horn pain-modulating BDNF/neuropathic pathway included SYNPR, NTF3 and RBFOX1. In an independent cohort BDNF was significantly elevated in patients with constant-severe pain. Extension and expansion of this exploratory study may identify pathway- and mechanism-dependent targets for individualized pain treatments in CP patients. PERSPECTIVE: Pain is the most distressing and debilitating feature of chronic pancreatitis. Yet many patients with chronic pancreatitis have little or no pain. The North American Pancreatitis Study II (NAPS2) includes over 1250 pancreatitis patients of all progressive stages with all clinical and phenotypic characteristics carefully recorded. Pain did not correlate well with disease stage, inflammation, fibrosis or other features. Here we spit the patients into groups with the most severe pain and/or chronic pain syndromes and compared them genetically with patients reporting mild or minimal pain. Although some genetic variants associated with pain were expressed in cells (1) of the pancreas, most genetic variants were linked to genes expressed in the nervous system cells associated with (2) neural development and axon guidance (as needed for the descending inhibition pathway), (3) psychiatric stress disorders, and (4) cells regulating sensory nerves associated with BDNF and neuropathic pain. Similar and overlapping genetic variants in systems 2 -4 are also seen in pain syndromes form other organs. The implications for treating pancreatic pain are great in that we can no longer focus on just the pancreas. Furthermore, new treatments designed for pain disorders in other tissues may be effective in some patient with pain syndromes from the pancreas. Further research is needed to replicate and extend these observations so that new, genetics-guided rational treatments can be developed and delivered.

Humans↗
PubMed1978

Cystinuria genotypes predicted from excretion patterns.

Genotypes of 17 patients with cystinuria were predicted from data based on excretion rates of the families' obligate carriers. The methodology differed from that used by other investigators as it did not employ intestinal biopsy studies or loading dose measurements. The Type I form was more common than either Type II or Type III and frequently occurred in combination to give compound heterozygous genotypes with the Type III form.

Adolescent↗
PubMed2026

Distinct HLA Associations for Antibody Multireactivity With Citrulline-Containing Type II Collagen Epitopes Versus More Limited Antibody Reactivity With Citrulline-Containing IgG Epitopes in Rheumatoid Arthritis.

OBJECTIVE: Anticitrullinated protein antibodies (ACPAs) in rheumatoid arthritis (RA) can be promiscuous, with cross-reactive binding to many antigens containing short motifs, or private with little cross-reactivity. Also, ACPA reactivity patterns differ among patients with RA, including for motif-containing epitopes in important self-antigens like collagen and IgG (bound by RA-associated rheumatoid factors [RFs]), with limited understanding of the underlying mechanism. The objective of this study was to determine if HLA alleles associate with ACPA reactivity patterns. METHODS: For 100 ACPA+RF+ participants with RA, serum IgG binding was quantified by enzyme-linked immunosorbent assay to 10 citrulline-containing peptides derived from Type II collagen and IgG1 (nine with motifs), and HLA loci were genotyped. Also, antibody and serum multireactivity were evaluated. HLA alleles present differentially in RA participants with high versus low IgG binding to specific peptides, as well as with multireactivity versus limited reactivity were identified by Fisher's exact test. RESULTS: Serum IgG multireactivity for citrulline-glycine motif-containing collagen peptides was high, at least partially due to promiscuous antibodies. HLA-DQA1*01:02 was present in more participants with anticitrullinated collagen antibodies and multireactive sera. In contrast, serum multireactivity was low for IgG1-derived peptides due at least in part to more private antibodies. Shared epitope-containing HLA-DRB1*04:01 was present more frequently in participants with RA-associated RFs irrespective of the citrulline-serine motif and less frequently in participants with anticitrullinated collagen antibodies. Several HLA alleles associated with specific antibody reactivities. CONCLUSION: Different HLA alleles may contribute to the different reactivity patterns of promiscuous anticitrullinated collagen antibodies and more private RA-associated RFs.

Humans↗