PubMed Health⌕ Search

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 91 records · Page 5Linked to original sources
PubMed1985

Clinical symptoms and HLA antigens in a family with Reiter's disease.

A clinical and immunogenetic study was performed on a three-generation family with Reiter's disease (RD). Twelve of 56 members of the family (33 clinically examined) including one in-law, had symptoms of arthritis, urethritis, conjunctivitis, uveitis, and/or mucocutaneous manifestations, but only one had the complete triad of Reiter's syndrome (RS). Radiographic sacro-iliitis was found in 7 individuals, and monoarticular onset was reported in 5 out of 7 with peripheral arthritis. HLA B27 was found in 26 of the 37 family members who were tissue typed (including one in-law). All individuals with RD were B27-positive. Seven different B27 phenotypes were identified. This finding suggests that RD is associated with the B27 antigen itself, and not to a gene closely linked to B27. From a pedigree analysis of this family an autosomal dominant inheritance with incomplete penetrance or multifactorial inheritance seemed the most probable alternatives. The family history is a useful adjunct in the diagnosis of RD.

Adolescent↗
PubMed1979

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↗
PubMedDate not supplied

Inheritance of low density lipoprotein subclass patterns in familial combined hyperlipidemia.

The inheritance of low density lipoprotein (LDL) subclass patterns was investigated in 234 members of seven large kindreds with familial combined hyperlipidemia (FCHL), a disorder characterized by elevated LDL cholesterol and/or triglyceride and increased coronary disease risk in families. Analysis of LDL subclasses by nondenaturing gradient gel electrophoresis showed a predominance of large, buoyant LDL particles (pattern A) in 71% of the family members and a predominance of small, dense LDL particles (pattern B) in 29% of family members. Based on complex segregation analysis, pattern B appeared to be inherited as an autosomal trait with either a dominant or an additive mode of inheritance and a small, but significant, multifactorial inheritance component. The proposed allele for pattern B was common (frequency = 0.3), and reduced penetrance was observed among men under age 20 and among women under age 50. These results in these FCHL families are consistent with those from a previously reported population-based sample of families, in which pattern B showed an apparent dominant mode of inheritance. In that study, reduced penetrance was observed for men under age 20 and for premenopausal women, but a somewhat lower allele frequency was found for pattern B (0.25). In the FCHL family members, LDL subclass pattern B was associated with significantly increased plasma levels of apolipoprotein B and triglyceride and decreased high density lipoprotein cholesterol. In comparison with a group of controls, the FCHL family members with pattern A had similar mean triglyceride levels, but higher mean apolipoprotein B. Thus, in families with FCHL, a predominance of small, dense LDL particles appears to be inherited as a common, single-gene trait, which is closely associated with the higher plasma triglyceride levels found in these families. The increased plasma apolipoprotein B levels found in FCHL cannot, however, be accounted for by this proposed locus.

Adult↗
PubMed2000

Genetic heterogeneity of non-specific mental retardation.

OBJECTIVE: To explore genetic patterns of non-specific mental retardation (NSMR). METHODS: Using segregation analysis, Finney method and Falconer method, the authors studied 157 pedigrees with NSMR selected in a population survey in Shandong province. RESULTS: Ux U multiplex families may accept the autosomal recessive inheritance, Ux U total families is the autosomal recessive inheritance while it may be the multifactorial inheritance with major-gene effect, the frequency of sporadic cases is approximately 46%; Ux A mating families may keep the incomplete penetrance in autosomal dominant inheritance. CONCLUSION: The genetic pattern of NSMR has the genetic heterogeneity.

Female↗
PubMed1978

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↗
PubMed1991

Genetic influences in autism.

Two behavior genetic research strategies have been utilized to understand gene influences in autism. There is overwhelming evidence for gene involvement, although an exact mode of inheritance has not yet been elucidated. Family and twin studies illustrate that the clinical phenotype of autism is not sufficient to characterize the underlying genotype(s) involved. Exactly what should be included in the phenotype remains elusive. Cognitive and social deficits are indicated as milder variants of the autism phenotype, but precisely how to define these deficits requires further research. Furthermore, more complex models of inheritance (e.g., two-locus models--multifactorial and major gene) may be necessary to explain gene influences in autism. Genetic heterogeneity is indicated in autism, with an X-linked disorder, fragile X, and an autosomal dominant disorder, tuberous sclerosis, together accounting for perhaps 8% to 11% or more of cases of autism. Differences in family patterns (i.e., recurrence risks) of neuropsychiatric disorders between autism with and without mental retardation or other clinically defined groups (e.g., males and females) are suggested. Whether these differences represent genetic heterogeneity or multifactorial inheritance with varying thresholds (e.g., of severity or sex differences) cannot be distinguished on the basis of the data available to date. Autosomal recessive inheritance is suggested in a subgroup of families with autism, but the proportion of all autism that may be accounted for by autosomal recessive inheritance is unknown. Evidence exists that stoppage occurs in families with autism, however, and this can affect accurate estimates of segregation ratios when not taken into account. Future family studies need to report (1) exact ascertainment schemes and specification of probands and (2) sex and birth order of affected siblings, including sibship size, so that data may be pooled and such effects can be tested. Investigations of populations with fragile X or tuberous sclerosis as well as those with autism (without known genetic disorders) will identify the etiologic basis of these associations. Such associations may be due to linkage of genes underlying autism and those underlying the known genetic disorders (i.e., linkage disequilibrium) or shared brain pathophysiology or merely shared overt behaviors. Until such mechanisms are elucidated, we can use only empiric risk figures in genetic counseling situations of autism, assuming that no known genetic or environmental cause is identified. Pooling available data from family and twin studies, the following empiric risks are suggested for genetic counseling purposes. An average sibling risk (frequency of affected siblings among all siblings) based on pooled data is 3% (i.e., 57/1698).(ABSTRACT TRUNCATED AT 400 WORDS)

Autistic Disorder↗
PubMed1984

Psoriasis in first-degree relatives of psoriatic twins.

Analysis of the presence of psoriasis in all first-degree relatives of psoriatic twin probands, 38 monozygotic (MZ) and 24 dizygotic (DZ), has been performed in order to clarify if genetic heterogeneity might be present (the twin-family method). The probands were derived from a population based sample of like-sexed twin pairs. An almost identical frequency of psoriasis in parents, siblings and children, with no sex difference, was found. By comparisons of empirical risk figures for psoriasis in first-degree relatives of concordant as compared with discordant MZ probands and HLA-B 13 and/or HLA-B 17 positive MZ probands compared with MZ probands lacking these antigens, no clue to the presence of genetic heterogeneity was found. An almost identical risk in co-twins and ordinary siblings of DZ-probands was found. The data were incompatible with autosomal recessive or X-linked inheritance, but not incompatible with autosomal dominant inheritance with reduced penetrance or with multifactorial inheritance.

Adolescent↗
PubMed1996

The inheritance of factors associated with joint mobility.

From a sample of 1,500 individuals belonging to 442 migrant nuclear families from northeastern Brazil, information on the interphalangial mobility was obtained: (a) the grades of extension of both the right and left thumbs and (b) the angle (in degrees) formed by the distant and proximal phalanx of the thumb. The first principal component of these variables was estimated and called "extensibility." A negative association of extensibility and age, as well as with inbreeding, was detected. Complex segregation analysis was applied to extensibility and both a multigenic mechanism and an extra transmissible component were detected. Mendelian inheritance was rejected, while a model with multifactorial inheritance, together with a factor that is inherited with a transmission probability different from 1/2 (tau = 0.63), was not rejected. These findings were supported by path analysis, which showed an important biologic inheritance (h2 = 0.675) and the existence of a small but significant cultural component (c2 = 0.003). The observed "inbreeding" effect, therefore, could not be attributed to a genetic mechanism and probably is the effect of concomitant environmental variability.

Brazil↗
PubMedDate not supplied

Microtia: a clinical and genetic study at the National Institute of Pediatrics in Mexico City.

BACKGROUND: Microtia is a malformation of the ear with extreme variability of expression. It is generally seen as an isolated malformation. However, some authors consider it to be a minimal manifestation of the oculo-auriculo-vertebral spectrum (OAVS), where, in addition, there are facial, vertebral, and renal abnormalities, among others. METHODS: A total of 145 pediatric patients with unilateral or bilateral microtia not considered as part of a syndrome were studied. All patients were subjected to an intentional clinical examination, a familial history, and radiographic imaging studies for ruling out associated malformations. Patients were classified into two groups: group 1 (60%), with isolated microtia; and group 2 (40%), considered as OAVS, with microtia associated with hemifacial skeletal microsomia, vertebral and/or renal malformations. RESULTS: No significant differences were found between the groups when the following variables were compared: gender; presence of unilateral or bilateral microtia; atretic external auditory canal; presence of preauricular tags; hearing loss of any type, and affection of the seventh cranial nerve, as well as associated malformations of other organs or systems. There were significant differences in relation to the presence of soft-tissue hemifacial microsomia, more frequently seen in patients with OAVS, because the majority of these patients had bone microsomia. Over 66% of the cases were sporadic and the rest were familiar. In 28.3% of the cases, the history suggested an autosomal-dominant inheritance pattern, and in 5.5%, an autosomal-recessive inheritance pattern, although in some familial cases, multifactorial inheritance could not be ignored. Some members in several families had isolated microtia, and others had mild characteristic manifestations of OAVS. CONCLUSIONS: Our results support the hypothesis that isolated microtia is a minimal expression of OAVS. Therefore, it is recommended that patients with microtia be subjected to intentional studies that search for malformations and physical examinations of first-degree relatives for adequate genetic counseling and management.

Adolescent↗
PubMed1983

Familial hemifacial microsomia.

Hemifacial microsomia, a relatively distinct clinical form in the Facio-Auriculo-Vertebral Spectrum is generally thought to be a sporadic event, although infrequent familial occurrences have been reported. In this communication, we describe a family with three males and two females in two successive generations affected with hemifacial microsomia. The pedigree is most compatible with autosomal dominant inheritance, although X-linked dominant or multifactorial inheritance cannot be excluded.

Ear, External↗
PubMed1987

Maternal transmission of congenital heart diseases: new recurrence risk figures and the questions of cytoplasmic inheritance and vulnerability to teratogens.

A review of 8 studies involving 3,996 offspring of parents who have congenital heart disease revealed that the risk for all defects was substantially higher if the affected parent was the mother rather than the father. The risk ratio ranged from a high of 6.39 for aortic stenosis to a low of 1.48 for patent ductus arteriosus, and the ratio was statistically significant in aortic stenosis (p = 0.025) and ventricular septal defect (p less than 0.001). Despite the relatively large number of cases, there were still too few patients to reveal statistical significance for a malformation such as atrioventricular canal, in which there were 5 affected offspring among 36 children of mothers who had atrioventricular canal and no affected children among 16 offspring of affected fathers (p = 0.12). The possible reasons for the preponderance of affected offspring of mothers with a congenital heart disease was studied in the context of various modes of inheritance and maternal physiology. The preliminary conclusion is that although many familial cases of congenital heart disease are compatible with multifactorial inheritance and vulnerability to teratogens, an important subset of cases, particularly in some high-risk families, may be better explained by cytoplasmic inheritance than by multifactorial or mendelian modes. Current genetic counseling should take into account the differences in risk to offspring of affected mothers while confirmation and further investigation proceeds.

Abnormalities, Drug-Induced↗
PubMed2002

[Genetics of autism].

Autism is a severe psychiatric disorder characterised by deficits in social interaction, disturbed communication and adherence to stereotype routines and interests. Nowadays it is completely clear that this disorder has a biological basis and many observations show strong genetic determination of autism. The importance of genetic factors is supported by frequent association of this disorder with known hereditary diseases or with various chromosomal aberrations, by high concordance of the disorder in monozygotic twins, higher risk for the siblings of autistic patients and also by the frequent occurrence of milder symptoms of the autistic spectrum in more distant relatives. All these findings show that the autistic phenotype results from unfavourable combination of alleles of several genes in interplay with factors of the environment. This model of multifactorial inheritance of autism serves at present as the starting point for the search for predisposing genes in the human genome. The association is tested between autism and alleles of candidate genes selected based on known biochemical and physiological role of their protein products, or based on their location close to recurrent chromosomal rearrangements or in regions identified by whole-genome linkage analyses. Studies of most of these genes have not yielded clear-cut results yet, but the participation of some of them in the aetiology of autism is possible.

Autistic Disorder↗
PubMed2003

Reduced folate carrier polymorphism (80A-->G) and neural tube defects.

Transport of folates in mammalian cells occurs by a carrier-mediated mechanism. The human folate carrier (RFC-1) gene has been isolated and characterized. Within this gene, a common polymorphism, 80A-->G, changing a histidine to an arginine in exon 2 (H27R), was recently identified. Defects in folate metabolism, such as defective carrier molecules, could be implicated in the etiology of neural tube defects (NTDs). In the present case-control study, we recruited 174 Italian probands with nonsyndromic NTD, 43 mothers, 53 fathers and 156 control individuals and evaluated the impact of RFC-1 variant on NTD risk. A statistically significant risk was calculated for the 80GG genotype of the NTD cases (OR=2.35; 95% CI 1.21-4.58) and mothers (OR=2.74; 95% CI 0.92-8.38). On the contrary, the heterozygous genotype of the mothers and both heterozygous and homozygous genotypes of the fathers did not seem to be significant NTD risk factors. Furthemore, according to the multifactorial inheritance of NTDs, we demonstrated that the combined genotypes for MTHFR 1298A-->C and RFC-1 80A-->G polymorphisms of cases resulted in greater NTD risk than heterozygosity or homozygosity for RFC-1 80A-->G variant alone. Conversely, our data provide no evidence for an association between NTD phenotype and combined MTHFR C677T/RFC-1 A80G genotypes. Moreover, here we describe the combinations of the two MTHFR polymorphic sites (677CT and 1298AC) with RFC-1 genotypes. We found that both patients and controls could have at most quadruple-mutation combinations. Interestingly, 27% (7/26) of the mothers and 18.75% (30/160) of the cases genotyped presented four mutant alleles in comparison with 8.5% (11/129) of the controls. Finally, the frequency of NTD cases and mothers carrying combined heterozygosity for the two MTHFR polymorphisms and RFC-1 80GG homozygosity (677CT/1298AC/80GG) (cases=11.3%; mothers 11.5%) was increased compared with controls (1.6%). Altogether, our findings support the hypothesis that RFC-1 A80G variant may contribute to NTD susceptibility in the Italian population.

Adult↗
PubMed1984

Familial incidence of congenital anorectal anomalies.

We describe two families with pedigrees over three and two generations with nine members affected with anorectal malformations. Both pedigrees are compatible with autosomal dominant inheritance with variable penetrance and expression or with multifactorial inheritance with a high genetic load. The recurrence risk is thought to be in the range of 10% to 20% for first degree relatives of affected members.

Adolescent↗
PubMed1975

A difference between the inheritance of classical juvenile-onset and maturity-onset type diabetes of young people.

A difference in the inheritance of diabetes has been shown between the families of twenty-six patients with maturity-onset type diabetes of young people (MODY) and families of thirty-five patients with classical juvenile-onset diabetes (JOD). In the families of MODY: 1) twenty-two of twenty-six (85 per cent) propositi had a diabetic parent; 2) 46 per cent of families showed direct vertical transmission of diabetes through three generations; 3) of forty-seven tested siblings twenty-five (53 per cent) had latent diabetes; 4) the diabetic phenotype in the families was consistent, most affected individuals having a noninsulin requiring type of disease. These findings are compatible with autosomal dominant inheritance of MODY, although they do not exclude multifactorial inheritance. In contrast, in the families of JOD: 1) only four (11 per cent) of propositi had a diabetic parent; 2) three generation inheritance was found in only two (6 per cent) of JOD families, and 3) of seventy-four tested siblings eight (11 per cent) were diabetic. This difference provides further evidence of genetic heterogeneity in diabetes mellitus and indicates that there is a need for careful definition of the phenotype of diabetes in populations in which the genetics of diabetes is to be analyzed. Diabetes 24:44-53, January, 1975.

Adolescent↗
PubMed2000

Segregation analysis of urinary albumin excretion in families with type 2 diabetes.

Elevated urinary albumin excretion (UAE) is a predictor of the development of nephropathy and cardiovascular mortality. To study whether genetic factors may determine UAE, we examined familial aggregation of UAE in 96 large multigenerational pedigrees ascertained for type 2 diabetes. A total of 1,269 subjects had UAE measured as the urinary albumin-to-creatinine ratio (ACR). This included 630 subjects with type 2 diabetes and 639 subjects without diabetes. A significant correlation (Spearman's correlation 0.34, P < 0.001) was found between the median ACR values determined separately in nondiabetic and diabetic members of the same family. To determine whether this familial aggregation of ACR could be explained by the transmission of 1 or more major genes and thus be suitable for gene mapping studies, segregation analyses were performed. In these analyses, ACR was modeled as a continuous trait with the inclusion of age, sex, and duration of diabetes as covariates. Likelihood ratio tests were performed to test competing hypotheses, and Akaike's information criterion was used to determine the most parsimonious models. The Mendelian model with multifactorial inheritance was supported more strongly than Mendelian inheritance alone. These analyses suggested that the best model for ACR levels was multifactorial with evidence for a common major gene. When the analyses were repeated for diabetic subjects only, the evidence for Mendelian inheritance was improved, although a single major locus with additional multifactorial effects was more strongly supported. The results from the current study suggest that levels of UAE are determined by a mixture of genes with large and small effects as well as other measured covariates, such as diabetes.

Adult↗
PubMed1997

Analysis of 31 families with an apparently autosomal-dominant transmission of migraine with aura in the nuclear family.

We analyzed 31 families selected for an apparently autosomal-dominant mode of inheritance of migraine with aura (MA) in the nuclear family. The nuclear families were expanded with first- and second-degree relatives. All interviews were made by physicians experienced in headache diagnoses. The criteria of the International Headache Society were used. The population relative risk among children in nuclear families was similar to the estimated population relative risk of MA assuming an autosomal-dominant mode of inheritance. The population relative risk tended to decrease among first-degree relatives outside nuclear families and further among second-degree relatives. Both first- and second-degree relatives outside the nuclear families had a statistically significant lower risk of MA than expected. Thus, autosomal-dominant inheritance with or without reduced penetrance was unlikely. Autosomal-recessive inheritance was unlikely because of the unequal sex distribution. Other modes of inheritance were considered as well. Mitochondrial and X-linked inheritance were excluded because of paternal transmission. The female preponderance was too low to explain sex-influenced inheritance. We conclude that MA most likely has a multifactorial inheritance even in high-risk families with MA.

Adolescent↗