PubMed HealthSearch

SEARCH · PubMed Health

Results for “Multifactorial Inheritance”

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 19 recordsLinked to original sources

Prevention of inherited multifactorial diseases.

Among the inherited multifactorial diseases are included a number of the common chronic diseases of adults. Assignment of risks within high-risk families, based on both genetic and environmental factors, offers opportunity for prevention of a portion of the present chronic disease burden. The most realistic option for prevention must be assessed for each disease, since this varies from no options to a relatively simple decision to avoid a specific environmental risk factor. Attention to specific options for prevention is an aid to identifying areas of high priority research, such as (1) factors which influence compliance with preventive management, (2) the quality of the physician-patient relationship, (3) environmental monitoring and technics for assessing genetic susceptibility to environmental risks, and (4) education of physicians in the art of chronic disease prevention.

Breast Neoplasms

Multifactorial inheritance with cultural transmission and assortative mating. II. a general model of combined polygenic and cultural inheritance.

A general linear model of combined polygenic-cultural inheritance is described. The model allows for phenotypic assortative mating, common environment, maternal and paternal effects, and genic-cultural correlation. General formulae for phenotypic correlation between family members in extended pedigrees are given for both primary and secondary assortative mating. A FORTRAN program BETA, available upon request, is used to provide maximum likelihood estimates of the parameters from reported correlations. American data about IQ and Burks' culture index are analyzed. Both cultural and genetic components of phenotypic variance are observed to make significant and substantial contributions to familial resemblance in IQ. The correlation between the environments of DZ twins is found to equal that of singleton sibs, not that of MZ twins. Burks' culture index is found to be an imperfect measure of midparent IQ rather than an index of home environment as previously assumed. Conditions under which the parameters of the model may be uniquely and precisely estimated are discussed. Interpretation of variance components in the presence of assortative mating and genic-cultural covariance is reviewed. A conservative, but robust, approach to the use of environmental indices is described.

Computers

Allelic restriction: a biologic alternative to multifactorial threshold inheritance.

Contrary to the argument regarding the conservatism of the multifactorial threshold model for describing the inheritance of congenital malformations, little biological insight has resulted from the series of tautological, albeit grandiose, mathematical assumptions currently comprising the basis for this hypothesis. The working hypothesis of this presentation is to apply the "allelic restriction" model to the genesis of common human congenital malformations. New population data concerning isolated cleft palate closely fit the predictions of the proposed hypothesis. Recognising the heterogeneity of cleft palate as well as other common congenital malformations (namely, the difference between phenocopies, definable syndromes, and true hereditary cases), the "allelic restriction" model accords with the apparent greatly "reduced penetrance" of the heriditary cases. This model is meant to apply only to those congenital malformations which have both a high population frequency and a relatively small number of families showing an atypical type of vertical transmission.

Adult

Familial occurrence of gastroschisis. Four new cases and review of the literature.

In two unrelated families, there was familial occurrence of gastroschisis. In one family, a boy and girl were affected and there was a family history of stillbirth, abortion, prematurity, and esophageal obstruction. In the second family, two boys were affected and there was a family history of spontaneous abortion, inguinal hernia, and umbilical hernia. The recurrence of gastroschisis, generally considered a sporadic congenital effect, suggests that the condition may be genetic in nature. Furthermore, the pedigree of one of the families suggests that gastroschisis may be a severe expression of umbilical hernia or other abdominal wall defects. Autosomal dominant inheritance with variable expressivity or multifactorial inheritance may explain the occurrence of gastroschisis in the two families. Thus, a family history of abdominal wall defects may increase the risk for gastroschisis.

Abdominal Muscles

Genetic counseling and the pediatrician.

The assistance of the pediatrician, following diagnosis of a child with a genetic disorder, towards his family consists today in giving genetic counseling for prevention of recurrence in future pregnancies. The process of genetic counseling, once the right diagnosis is made, should not be difficult as concerns Mendelian inheritance. It is well known that several chromosomal disorders follow the rules of Mendelian inheritance. The theory of polygenic or multifactorial inheritance may create problems in the accurate estimation of risks. An effort is made to discover the mechanisms of genetic "predisposition" or the adverse environmental factors, in order to minimize the occurrence of such disorders. An important tool in prevention of several genetic disorders, which should be mentioned in genetic counseling, is prenatal diagnosis.

Chromosome Aberrations

Novel Protein-Altering Variants in Cleft Genes Transmitted in Families With NSCL±P.

BACKGROUND: Pathogenic protein-altering variants play a role in the etiology of nonsyndromic cleft lip with or without palate (nsCL±P), one of the most common craniofacial anomalies. However, the genetic basis of many cases remains unclear, complicating risk prediction for affected families. PURPOSE: This study utilized whole-genome sequencing (WGS) of 150 case-families with nsCL±P from sub-Saharan Africa to identify pathogenic risk variants. STUDY DESIGN, SETTING, SAMPLE: This study utilized whole-genome sequencing (WGS) of 150 case-families with nsCL±P from sub-Saharan Africa to identify risk variants. PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE: Genetic variants. MAIN OUTCOME VARIABLES: Nonsyndromic cleft lip with or without palate (nsCL±P). ANALYSES: Genomes were sequenced at a mean ×30 coverage, and variants were prioritized using CADD (≥20), REVEL (≥0.5), and ACMG/AMP clinical significance criteria. RESULTS: We identified pathogenic protein-altering variants in CHD7 (p.Arg1345His), LRP2 (p.Asp3245Asn), RYR1 (p.Arg2163Leu, p.Pro2903Thr), SHH (p.Met114Val), and WNT3 (p.Ser112Pro) highlighting the role of hedgehog signaling pathway (FDR=5.32e-12) in nsCL±P. These variants were inherited from unaffected parents suggesting an incomplete penetrance of the variant effect. Although mouse data showed that knockout of these genes produces cleft phenotypes, in vivo studies will help us better understand how the consequences of these variants differ from benign mutations. The presence of these protein-altering variants in unaffected parents-incomplete penetrance, provides additional evidence supporting the trait complexity. CONCLUSIONS AND RELEVANCE: This study identified rare, pathogenic protein-altering variants in genes involved in key developmental pathways in African families affected by nsCL±P. These findings highlight the critical role of the hedgehog signaling pathway and related networks in the etiology of nsCL±P. These findings underscore the importance of whole-genome sequencing in genetically diverse populations to uncover novel risk variants. These findings enhance our understanding of the genetic etiology of nsCL±P, particularly in under-represented African populations and support the multifactorial inheritance and the involvement of developmental pathways, such as hedgehog signaling in the etiology of clefting.

Humans

Bilateral renal agenesis (Potter's syndrome) in two consecutive infants.

Bilateral renal agenesis is a relatively rare congenital anomaly; its frequency is 1 : 3000-4000 deliveries, with a remarkable predominance of male infants. This anomaly is most often found in combination with characteristic facial features ('Potter's face') and pulmonary hypoplasia, the combination being known as Potter's syndrome. In the course of pregnancy an increasing oligohydramnios becomes manifest; during labor, virtual absence of amniotic fluid is found in most cases. This oligohydramnios should alert the obstetrician to suspect Potter's syndrome; serial ultrasonography may confirm the diagnosis. Most affected children are born alive but die within a few hours due to respiratory difficulties caused by the pulmonary hypoplasia. Despite the remarkable facial characteristics of these infants, it was only in a small minority that the diagnosis was considered before autopsy. This stresses the need for a full post-mortem examination in all cases of perinatal death. The etiology is still uncertain, though multifactorial inheritance is the most likely. As a consequence, the recurrence risk is not negligible; the small number of 'familial occurrence' observations, however, does not allow estimation of a risk figure. Genetic counseling is indicated in any family giving birth to a child with bilateral renal agenesis. A family is described in which two consecutive male infants with bilateral renal agenesis were born alive and survived 19 and 38 h.

Abnormalities, Multiple

Familial congenital diaphragmatic hernia: prenatal diagnostic approach and analysis of twelve families.

Congenital diaphragmatic hernia is generally recognized as a sporadic malformation with little or no risk of recurrence. A family with three affected individuals in two generations is presented. In addition, new prenatal diagnostic techniques including ultrasonography and amniography are discussed. A comparison of associated physical characteristics in isolated versus twelve familial cases of diaphragmatic hernia is presented. In the familial group, there was a higher incidence of affected males (M:F ratio = 2.1 versus 0.67), a higher incidence of bilateral defects (20% versus 3%) and a lower incidence of additional life-threatening malforamtions 3.6% versus 47%). Analysis of available pedigree data favors multifactorial inheritance with a high male: female sex ratio as the most probable mode of transmission.

Abnormalities, Multiple

The use of multiple thresholds and segregation analysis in analyzing the phenotypic heterogeneity of multifactorial traits.

(1) Three models based on multifactorial inheritance are introduced to account for phenotypic heterogeneities. These models are used to determine whether subforms of a triat are: (a) different degrees of the same process, (b) non-familial environmental variants of the same process, and (c) independently transmitted processes. (2) The parameters of each model consist of two population prevalences and either one, two, or three correlation coefficients which reflect the three hypotheses given above. The models are formulated so that a likelihood ratio test may be performed to discriminate between them. (3) The following types of analyses are described: (a) analysis of prevalence data with separate population prevalence estimates, (b) analysis of prevalence data with the proband a parent with specified spouse, (c) analysis of prevalence data with the proband an offspring with specified parents, and (d) the full segregation distribution of families using Complex Segregation Analysis. (4) When compared with the Analysis of Prevalences, Complex Segregation Analysis has the following advantages: (a) the number of degrees of freedom for parameter estimates is greater and separate estimates of the population prevalences are not necessary, (b) standard errors of the parameters are smaller, and (c) the power to discriminate models is increased. (5) Phenotypic heterogeneities such as age of onset, severity, and sex effect can be more completely understood by the methods of analyses described above. The nosology of familial disorders can also be clarified, and environments relevant to the transmission of the trait can be detected. This approach is particularly suitable for the analysis for behavioural traits since it does not require the assumption that environmental effects common to relatives be ignored. (6) Finally, our experience indicates that incorporating both prevalence and pedigree data into a single analysis decreases the time required to perform the analysis.

Environment

Combinatorial multiomic analysis from a pedigree of Sox10Dom Hirschsprung mice identifies multiple high confidence candidate modifiers of Enteric Nervous System development.

Hirschsprung disease (HSCR) is characterized by absence of enteric ganglia (aganglionosis) along variable lengths of the distal intestine. This disorder results from deficient colonization of fetal intestine by enteric neural crest-derived cells (ENCDCs). HSCR exhibits complex, multifactorial inheritance with penetrance and severity varying widely even within families. SOX10 is among causal genes that predispose to aganglionosis. Yet, how gene interactions influence severity of HSCR aganglionosis is not understood. Prior mapping of aganglionosis modifiers was achieved in a standard F1-intercross utilizing the Sox10Dom HSCR mouse model. Here we deploy a novel strategy of genotyping an extended pedigree pedigree of Sox10Dom mice on a mixed genetic background. GWAS in this pedigree points to novel aganglionosis modifier intervals with replication and refinement of prior modifier regions. Complementary omics analysis of the developing Enteric Nervous System (ENS) enabled identification of multiple high-priority candidate genes within these modifier intervals based on gene expression, chromatin accessibility, and presence of conserved SOX10 binding motifs. We implemented a prioritization pipeline for ranking potential modifiers that generated candidate lists including several well-known for effects on ENS development as well as multiple novel genes. Among the novel genes, Dach1 ranked as a top priority candidate gene for modifying migration of ENCDCs and thus influencing aganglionosis severity. The results identify genome intervals with intrinsic genes that are logical candidates for modifying Sox10Dom aganglionosis severity. We also note that several human orthologs to aganglionosis modifier candidate genes are within linkage disequilibrium blocks containing genetic variants associated with human gut motility disorders, which offers opportunity for gaining biological insight into human HSCR severity.

Animals

Polygenic risk score and its role in cancer susceptibility.

BACKGROUND: Polygenic risk score (PRS) has the ability to stratify inherited susceptibility to cancer and, as a complement to monogenic testing, can identify individuals at increased genetic risk even when no pathogenic variant is detected in high- or moderate-penetrance genes. It reflects the combined additive effects of a large number of low-penetrance variants across the genome, and represents a continuum of genetic susceptibility with an approximately normal distribution. Clinically relevant differences are typically observed in individuals in the highest and lowest percentiles of the PRS distribution, while relative risk gradients depend on the cancer type, the specific PRS model, and the reference population used. PRS is not a single test but rather a family of statistical models that differ in their design, predictive performance, and transferability across populations, underscoring the need for external validation and population-specific calibration of absolute risk. Broader implementation is thus still held back by differences between individual PRS models, limited transferability, and the lack of harmonized guidance on indication, reporting, and clinical decision-making. Consequently, clinical use in the European Union remains largely confined to pilot studies and local projects. Within these initiatives, PRS is most commonly applied in two main ways - either as a triage tool for intensified diagnostics or screening in higher-risk groups, or as a component of multifactorial absolute-risk models (e. g. BOADICEA/CanRisk) that integrate PRS with other risk factors such as pathogenic variants in moderate-penetrance genes (e. g. ATM or CHEK2), family history, or lifestyle factors. By refining absolute-risk estimates, PRS may shift individuals across clinical decision thresholds for more intensive surveillance and preventive strategies. AIM: This review summarizes the principles of PRS, the main sources of variability between models, and its potential applications in risk stratification and personalized cancer screening. It also addresses limitations in transferability, the need for calibration, and the currently limited evidence for improvements in hard clinical outcomes.

Humans

A genetic study of febrile convulsions.

307 probands with febrile convulsions classed as the simple type (131 children) and the complicated type (176 children) were genetically analyzed. There was a tendency toward familial aggregation of febrile convulsions, and genetic involvement was suggested. The multifactorial mode of inheritance best agreed with the observations. (1) The ratio of incidence of febrile convulsions in siblings of probands in the present study (19.9%) to the incidence in the general population (2.9%), i.e., 6.85, was rather close to the expected ratio of 5.87 from the multifactorial inheritance system. (2) The incidence in siblings tended to be higher when either or both of their parents had a history of febrile convulsions. In 2-child families where the first child was affected, the incidence in the second child tended to increase in parallel with the increasing incidence in parents. (3) The incidence in siblings was higher if probands were males. (4) The heritability, when estimated by Falconer's procedure, was as high as 76%, showing that febrile convulsions are strongly genetically predisposed. These findings were more distinctly observed in the simple type than in the complicated type.

Adult