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 1,333 records · Page 74Linked to original sources

Acquired von Willebrand syndrome--report of 10 cases and review of the literature.

Acquired von Willebrand syndrome (AvWS) is a rare bleeding disorder with clinical and laboratory features closely resembling hereditary von Willebrand disease (vWD), arising in previously haemostatically normal individuals. We present a retrospective review of 10 cases with AvWS diagnosed over 17 years. The severity of the bleeding tendency varied from mild to severe forms. Multimers electrophoresis showed that 8/10 patients had a normal pattern similar to type 1 vWD, 1/10 had a type 2A vWD pattern (with absence of high and intermediate molecular weight multimers) and 1/10 had a type 3 vWD pattern. An inhibitor screen was performed in 6/10 patients and autoantibodies against von Willebrand factor were found in only two cases. The underlying cause/associated conditions were identified in 8/10 patients. Treatment of the bleeding diathesis was successfully achieved with desmopressin or clotting factor concentrates. Resolution of underlying hypothyroidism (in two cases) and multiple myeloma (in one case) led to normalization of the coagulation parameters. The report on this cohort of 10 patients with AvWS illustrates the complexity of AvWS and its multifactorial aetiology. A brief review of the recent literature on AvWS is also presented, with emphasis on the current opinions in pathogenesis and treatment. Acquired von Willebrand syndrome (AvWS) is an acquired bleeding disorder, characterized by a phenotype similar to the inherited von Willebrand disease (vWD), with a prolonged bleeding time and low plasma levels of factor VIII - von Willebrand factor (vWF) measurements. It occurs in patients with no family history of vWD, who present with recent onset of bleeding symptoms. AvWS appears to be associated mainly with lymphoproliferative disorders, immunological conditions and neoplasia. AvWS is a rare condition and it is difficult to conduct prospective studies, therefore it is important to document the experience with such cases. The aim of this paper is first, to report 10 cases of AvWS identified at our Haemophilia Centre during the past 17 years. Second, to present a brief review of the recent literature on AvWS - outlining the salient features, associated disorders, mechanisms of acquisition and the available options of treatment.

Adult↗

Methods for the study of the genetic determinants of diabetes and its complications.

Diabetes and its complications have a multifactorial etiology that includes both environmental and genetic factors. This makes the aim of finding susceptibility genes difficult because of the contribution of multiple genes, the wide variety of environmental factors that are involved, the lack of a clear mode of inheritance, and the presence of genetic heterogeneity. Despite these problems, the recent advances in biotechnology offer the opportunity to dissect the genetics background of complex diseases. As in the case of other disorders, there are two major approaches to study the molecular genetics of diabetes: association studies and linkage studies in families. Association studies aim to identify susceptibility alleles through several approaches, the simplest of which is to compare unrelated cases and controls. While this study design is relatively easy, false positive results are common due to unrecognized differences between cases and controls. An alternative is to use family-based association studies such as the transmission disequillibrium test. While this approach requires more recruitment efforts, the chances of false positive results are minimized. In contrast to association studies, linkage studies are not targeted to single candidate genes, but rather investigate the cosegregation between large chromosomal regions and the disease. Linkage analysis can be performed by either non-parametric or parametric methods. Non-parametric studies are relatively easy to conduct and do not require previous knowledge of the mode of inheritance. However, they cannot detect genetic heterogeneity (i.e. the presence of multiple genes that contribute to diabetes in different families). In contrast, parametric methods require large pedigrees and the assumption of a model of genetic inheritance, but they can detect genetic heterogeneity. Several new diabetes loci and genes have already been identified through the strategies outlined above, and many more are expected to be found in the next few years with the completion of the Human Genome Project.

Chromosomes, Human, Pair 12↗

Predictive genetic testing -- new possibilities in determination of risk of complex diseases.

Predictive genetic testing offers the possibility to statistically determine the risk of inheriting a complex phenotype by establishing an individual s genotype for metabolic polymorphisms. Here we discuss the conditions under which a predictive test may be offered to a patient and the problems connected with it. Examples of predictive genetic testing for multifactorial diseases and drug responses are given. We describe in detail the association of the C677T polymorphism of methylentetrahydrofolate reductase gene with hyperhomocystinemia and folate levels, as an independent risk factor for cardiovascular disease, and the association of a polymorphism of the promoter of the 5-lipoxygenase gene and the response to leukotriene inhibitors in asthma. Prospective development of genomic medicine and its use in the study of complex traits will hopefully bring significant benefit to the population and enhance the prevention and therapy of common diseases.

Cardiovascular Diseases↗

DNA probes in human disease.

Nucleic acid probes are able to detect the presence of particular sequences in a sample down to the level of a few hundred molecules. They can discriminate between similar sequences to a resolution of better than one part in 10(9). They are capable of detecting inherited defects in tissues where the phenotype is not being expressed, and in cases where the biochemical aberration is not understood. They can characterize acquired diseases in somatic cells (both tumours and infectious agents). Additionally, they can be used to characterize multifactorial (either polygenic or requiring an environmental stimulus to interact with a genetic predisposition) diseases. Nucleic acid 'fingerprints' provide an unequivocal identification of the origin of cells which may be applied in criminal law, civil law, and in the follow up to bone marrow transplants. In spite of this tremendous potential, there is still a large gap between their use in research laboratories and their widespread application in pathology laboratories. There are two basic reasons for this. The first is the number of labour-intensive steps involved in the various 'blotting' techniques which greatly reduces the rate at which assays may be performed. The second is the need to use probes labelled with isotopes which are short-lived and may require stringent safety measures to be employed. Recent work both in this laboratory and elsewhere is designed to circumvent both these problems.

Biotin↗

Endometriosis: a genetic disease.

Endometriosis is a multifactorial disease affecting up to 15% of women of reproductive age. This condition is characterized by the presence and growth of endometrial cells outside the uterus. Susceptibility to endometriosis depends on complex interactions of immunologic, hormonal, environmental and genetic factors. Although familial inheritance plays a role, multiple candidate genes appear to be involved. New studies investigating the influence of genetic variants on endometriosis are published with increasing frequency. A number of technologies have emerged to facilitate progress in this field, including subtractive cDNA hybridization to identify secretory endometrial genes, DNA chip technology, differential display polymerase chain reaction, cytogenetics evaluation of endometriotic cells and tissues, and complementary methods in proteomics and informatics. One general approach to uncovering genes pivotal to endometriosis is to search systematically for perturbations in selective candidate genes or chromosomal regions using polymerase chain reaction. We describe here novel association studies on obvious candidates, including genes governing cancer susceptibility, hormone sensitivity or immunology. The assessment of mutations and polymorphisms may allow individualization of therapies as well as primary and secondary prevention strategies for endometriosis, aimed at high-risk populations.

Endometriosis↗

[Clinical and genetic studies of Alzheimer-type dementia].

The families of 128 probands with Alzheimer's disease (AD) and senile dementia (SD) were studied. Genetical and mathematical analyses were employed to estimate the clinico-genealogical findings. The genetic factors were found to be likely to make some contribution to the origin of Alzheimer-type dementia (ATD). The proportion of afflicted relatives considerably exceeded that of the above dementia patients. Two genetic models (monogenic and multifactorial) were tested. The limit estimations of genetic similarity between AD and SD manifestations both in the monogenic and multifactorial models denied the fact that there is a common major gene responsible for liability to Alzheimer-type dementias. The common gene modifiers were assumed to exist in AD and SD. In addition to the differences found between the types of inheritance in patients with these disease, the following features are: an oligogenic type of inheritance in SD and a quasi-dominant one with incomplete manifestations of homo- and heterozygotes in AD. Studies into the clinical polymorphism of Alzheimer-type dementias in hereditary cases enabled the authors to establish the genetically determined signs and the environmentally induced signs. The predisposing features (premorbid characteristic traits and specific features of mnemic and intelligence) were identified, which allowed the development of Alzheimer-type dementias to be predicted in 80% of women from hereditarily aggravated families.

Aged↗

Genetics and pharmacogenetics of osteoporosis.

Osteoporosis is a skeletal chronic multifactorial disease characterised by abnormal low bone mass and microarchitectural deterioration of bone tissue. This disorder, present in both sexes, related to environmental and genetic factors, is becoming a major public health problem in developed countries. It has a polygenic pattern of inheritance that complicates identification of disease genes [cytokines, calciotropic hormones, sex hormones pathway synthesis and their receptors, bone matrix proteins synthesis genes involved on estrogenic metabolism (CYP19) and LDL receptor-related protein 5 (LRP5) gene]. It is possible to identify associations between candidate genes polymorphisms and disease phenotype in population-based and case-control studies. This could give us promising data for earlier identification of osteoporosis susceptibility and fracture risk. Preventive therapy could be targeted to patients at risk of osteoporosis before fractures occur. Genetic polymorphisms are also starting to be used to predict drug response. A new era of pharmacogenetics represents an interesting prospective to identify the potential individuals to receive customised treatments.

Animals↗

The human genome sequence and the analysis of multifactorial traits.

The human genome probably codes for about 10,000 basic functional units, most of which are functionally related families of genes occurring in one or more closely linked clusters. This relatively limited complexity means that a knowledge of the complete gene sequence is well within our grasp and will be fundamental to the analysis of complex multifactorial traits, including all the major chronic human diseases. Genetic marker segregation among 'affected' individuals in a pedigree, however complex, can now be done by using the essentially unlimited collection of restriction fragment length DNA polymorphisms. This can, in principle, identify all the inherited components of any complex trait and, with a knowledge of the human gene sequence, identify their functional basis. Thus one can now envisage a complete genetic and functional analysis of all complex inherited traits, including the major chronic diseases, and normal variation in physical and behavioural attributes.

Chromosome Mapping↗

Neuroinflammatory perspectives on the two faces of Alzheimer's disease.

The amyloid plaques in Alzheimer's disease (AD) brains are co-localized with a broad variety of inflammation-related proteins (complement factors, acute-phase proteins, pro-inflammatory cytokines) and clusters of activated microglia. The present data suggest that Abeta deposits in AD brains are closely associated with a locally induced, non-immune mediated, chronic inflammatory response. Clinicopathological and neuroradiological studies show that activation of microglia is a relatively early pathogenic event that precedes the process of neuropil destruction in AD. Epidemiological studies indicate that polymorphisms of certain cytokines and acute-phase proteins that are colocalized with Abeta plaques, are genetic risk factors of AD. Epidemiological studies have also shown that the use of classical nonsteroidal anti-inflammatory drugs (NSAIDs) can prevent the risk of AD but clinical trials with anti-inflammatory drugs in AD patients were negative. These findings indicate that anti-inflammatory agents can be helpful in the prevention but not in the treatment of AD. So, pathological, genetic and therapeutic studies suggest that inflammatory mechanisms are most likely involved in the early steps of the pathological cascade. In the autosomal dominant inherited forms of AD the primary factor is the increased production of Abeta1-42 resulting into fibrillar Abeta deposition that elicits a brain inflammatory response. The etiology of the sporadic forms is yet unknown but this subtype is considered to be heterogeneous and multifactorial in its pathogenesis. Here we review the evidence that inflammation related events could be a critical etiological factor in certain forms of the sporadic AD.

Acute-Phase Reaction↗

HLA and autoimmune diseases: Type 1 diabetes (T1D) as an example.

Autoimmune diseases need to be considered at a genetic and mechanistic level. T1D is an autoimmune, chronic, multifactorial and polygenic disease characterized by the destruction of the pancreatic beta-cells associated with long term dysfunction of several organs and tissues. Mechanisms of susceptibility include epi-genetic and post-transcriptional effects that regulate transmission and expression of the inherited genes. The HLA complex, constitutes the most relevant region contributing 50% of the inherited risk for T1D. An additional 17 genes with variable but small effects have been described. In non-Caucasians, the presence of E-DRbeta1-74 and/or D-DRbeta1-57 are relevant in predisposition. The "Diabetogenic haplotypes" in Mexicans were DRB1*0301-DQA1*0501-DQB1*0201 (OR = 21.4); DRB1*0405-DQA1-*0301-DQB1*0302 (OR = 44.5) and the same DQA1/DQB1 with DRB1*0404/*0401 conferring lower risk, increasing (OR = 61.3) with an early age at onset and a heterozygote DR3/DR4 genotype. In most populations, the absence of D-57 and the presence of R-52 are important to the susceptibility, but in Hispanics, all DR4s (including the protective DRB1*0403/*0407/*0411) are in linkage disequilibrium with DQA1/DQB1 susceptibility alleles. Thus, susceptibility alleles in Latin American Mestizos are of Mediterranean ancestry whereas protective alleles are of Amerindian origin. In this review, we discuss the complexity of T1D and some aspects of prevention/intervention based on immunogenetics.

Autoimmune Diseases↗

Anticipation in Menière's disease.

The aetiology of Menière's disease (MD) remains obscure, but is likely to be multifactorial, one of the factors being a genetic predisposition. Forty-one families with more than one living member with MD were ascertained and affected and normal relations examined. Blood was collected and DNA extracted and stored. In these families the mode of inheritance is autosomal dominant, the penetrance of the mutation being about 60 per cent. Some of the family members exhibit a partial syndrome, vestibular symptoms predominating. Sporadic and familial cases exhibit the same clinical features. The striking finding is the phenomenon of anticipation, whereby with successive generations there is an earlier age of onset and a tendency to more severe manifestation. The inference, considering that the cells which regulate endolymph are of neuroectodermal origin, is that, like other neurodegenerative disorders which show anticipation, MD manifestation is likely to be related to trinucloetide expansion within a gene.

Adult↗

Pulmonary arterial hypertension.

Pulmonary arterial hypertension is a disease of the small pulmonary arteries characterized by vascular narrowing and increased pulmonary vascular resistance, which eventually leads to right ventricular failure. Vasoconstriction, vascular proliferation, remodeling of the pulmonary vessels, and thrombosis are all contributing factors to the increased vascular resistance seen in this disease. Pulmonary arterial hypertension develops as a sporadic disease (idiopathic), as an inherited disorder (familial), or in association with certain conditions (collagen vascular diseases, portal hypertension, human immunodeficiency virus infection, congenital systemic-to-pulmonary shunts, ingestion of drugs or dietary products, or persistent fetal circulation). The pathogenesis of pulmonary arterial hypertension is a complicated, multifactorial process. It seems doubtful that any one factor alone is sufficient to activate the necessary pathways leading to the development of this disease. Rather, clinically apparent pulmonary arterial hypertension most likely develops after a second insult occurs in an individual who is already susceptible owing to genetic factors, environmental exposures, or acquired disorders. Currently, there is no cure for pulmonary arterial hypertension but several novel therapeutic options are now available that can improve symptoms and increase survival.

Algorithms↗

Statistical analysis of histomorphological findings in medullary thyroid carcinoma: distinction between the different familial forms of the disease. G.E.T.C. Groupe d'Etude des Tumeurs a Calcitonine.

A multifactorial analysis of morphological findings was performed on 153 cases of medullary thyroid carcinoma (MTC). The aim of the study was to utilize histological criteria to discriminate between MTC associated with multiple endocrine neoplasia type 2A (MEN 2A) and that associated with the inherited MTC only syndrome. The presence of fusiform cells associated with several other markers seemed to be more predictive of MEN 2A. A comparison of inherited MTC only and sporadic MTC only showed fusiform cells to be significantly less common in inherited MTC only. These results suggest that the inherited MTC only syndrome is a distinct clinical and morphological entity. Further investigations are needed to confirm the findings and understand its implications.

Carcinoma↗

Identification and management of vascular risk: beyond low density lipoprotein cholesterol.

Vascular disease is basically an inherited metabolic disease. Eighty percent of individuals who develop disease have the same blood cholesterol levels as individuals who do not develop disease. With vascular disease pervasive throughout the world and current assessment techniques insufficient to identify those at risk, use of a multifactorial approach to vascular assessment is prudent. Assays are currently available that enable health care providers to determine risk beyond those traditionally used. These "novel" risk factors appear to be additive (Brown, 2001; Rader, 2000a, 2002; Superko, 1995), and when combined with traditional factors, LDL can be adjusted to prevent disease. In individuals with established disease, these factors can be instrumental in identifying an appropriate treatment protocol for halting the progression of disease. To date, the health care establishment as a whole has done a poor job of identifying and thoroughly treating cardiovascular risk. Even when risks were identified, often treatment protocols have not been aggressive enough to reach targeted goals (Hoerger, 1998; Jacobson, 2000; NHANES III, 2000). The unique role of the occupational health nurse offers an opportunity to follow a client during long periods of time. This is useful in establishing trust and getting to know the specific problems of each individual. The occupational health nurse, therefore, stands at the threshold of change for the client, easing and assisting the client to reach individual goals. This group of nurses can play a significant role in forging prevention and stamping out the number one killer of the American population.

Cardiovascular Diseases↗

Human genetics of the abdominal aortic aneurysm.

The results of recent studies suggest that genetic factors may be important in the pathogenesis of abdominal aortic aneurysms. In the present report, the apparent mechanisms of inheritance in 16 families with a total of 41 affected individuals are summarized. The results suggest that there may be both X-linked and autosomal dominant forms of the disease, with the X-linked variant as the more common type. A multifactorial mechanism cannot be ruled out from the results of the present data.

Aged↗

Dominant transmission of imperforate hymen.

OBJECTIVE: Imperforate hymen is an uncommon anomaly of the reproductive tract, occurring in approximately 0.1% of newborn females. The familial occurrence of imperforate hymen in a child, her mother, and her mother's monozygotic twin is reported. DESIGN: Case report. SETTING: Academic medical center. PATIENT(S): Three affected family members. MAIN OUTCOME MEASURE(S): Karyotype and pedigree analysis. RESULT(S): The proband, presenting with peritonitis, was evaluated at age 12 for imperforate hymen because this condition was diagnosed in her mother at age 14. At age 14, the mother's monozygotic twin was asymptomatic except for primary amenorrhea and was also demonstrated to have imperforate hymen. No other reproductive system abnormalities were known to be present in the remaining family members. Chromosomal structural analysis confirmed that the mother of the proband had no chromosomal abnormalities. CONCLUSION(S): The occurrence of imperforate hymen in two consecutive generations of a family is consistent with a dominant mode of transmission, either sex-linked or autosomal. Previously reported examples of siblings with imperforate hymen suggested a recessive mode of inheritance. Taken together, these cases suggest that imperforate hymen can be caused by mutations in several genes. This case highlights the importance of evaluating all family members of affected patients. Familial examples of other developmental anomalies of the female reproductive tract also suggest a multifactorial genetic etiology.

Adult↗

Genetics of lipoprotein disorders.

The study of lipoprotein metabolism has led to major breakthroughs in the fields of cellular physiology, molecular genetics, and protein chemistry. These advances in basic science are reflected in medicine in the form of improved diagnostic methods and better therapeutic tools. Perhaps the greatest benefit is the improved ability to identify at an early stage patients who are at high risk for atherosclerosis, providing clinicians the opportunity to proceed swiftly with intensive lipid-lowering therapy for the prevention of cardiovascular complications. Recent clinical trials have shown that such an approach is not only cost-effective but saves lives while improving the quality of life. They also emphasize the important role physicians can have in prevention. More than half of patients with premature CAD have a familial form of dyslipoproteinemia. This review of the genetics of atherogenic lipoprotein disorders underscores the importance of identifying major genetic defects. It also stresses the need to take into account multifactorial etiologies and clustering of risk factors, as well as gene-gene and gene-environment interactions in assessing the atherogenic potential of a lipid transport disorder. Table 2 summarizes the key points in the diagnosis, clinical implications, and treatment of the major inherited atherogenic dyslipidemias.

Diagnosis, Differential↗

The genetics of keratoconus.

Keratoconus is a relatively common, bilateral, non-inflammatory corneal ectasia. The aetiology of this condition is probably multifactorial, or it represents the final common pathway for a variety of different pathological processes. Although a familial history is present only in a minority of cases, one of the major aetiological factors is certainly genetic. This is evidenced by: the condition's familial inheritance; its discordance between monozygotic and dizygotic twins; and its association with other known genetic disorders such as Down's and Marfan's syndromes. In the keratoconic cornea, a possible genetic predisposition to increased sensitivity to apoptotic mediators by keratocytes has also been hypothesized. Differences in prevalence between ethnic groups have been identified. Recent advances in computerized topographic diagnostic techniques for keratoconus, including forme fruste keratoconus, enables higher accuracy in delineating abnormal from normal, and helps define study populations for genetic linkage studies. However, genetic heterogeneity and the phenotypic diversity of keratoconus means that genetic analysis continues to be a complex process. None the less, it is foreseeable that over the next decade, improved diagnostic techniques, in combination with molecular genetics, may reveal conclusive data on the precise nature of the genetic inheritance of keratoconus in specific populations. This review considers the evidence that suggests keratoconus is primarily an inherited condition, and examines research strategies aimed at unveiling the genetic predisposition, and the enigma of environmental influences on its phenotypic expression.

Cornea↗