Search results for "Alleles"
showing 10 items of 478 documents
Sex differences in allelic frequencies of the 5-HT2C Cys23Ser polymorphism in psychiatric patients and healthy volunteers: findings from an associati…
2000
Polymorphisms in the serotonergic system are believed to play a role in the etiology and treatment of different psychiatric illnesses. The 5-HT2C receptor gene is X-linked, with a frequent mutation at nucleotide 68 leading to a Ser-->Cys transition at amino acid 23. Recent studies have demonstrated an impaired function of 5-HT2C receptors and an increased production of the major noradrenergic metabolite 3-methoxy-4-hydroxyphenylethyleneglycol in the cerebrospinal fluid among the subjects carrying the Ser23 allele (Lappalainen et al., 1999). Biol. Psychiatry 46:821). We genotyped patients with alcohol dependence, panic disorder without agoraphobia, generalized anxiety disorder, narcolepsy an…
Primary HBB gene mutation severity and long-term outcomes in a global cohort of β-thalassaemia
2021
In β-thalassaemia, the severity of inherited β-globin gene mutations determines the severity of the clinical phenotype at presentation and subsequent transfusion requirements. However, data on associated long-term outcomes remain limited. We analysed data from 2109 β-thalassaemia patients with available genotypes in a global database. Genotype severity was grouped as β0 /β0 , β0 /β+ , β+ /β+ , β0 /β++ , β+ /β++ , and β++ /β++ . Patients were followed from birth until death or loss to follow-up. The median follow-up time was 34·1 years. Mortality and multiple morbidity outcomes were analyzed through five different stratification models of genotype severity groups. Interestingly, β0 and β+ mu…
Autoimmune polyglandular syndrome type 2 shows the same HLA class II pattern as type 1 diabetes†
2011
Autoimmune polyglandular syndrome (APS) type 2 is defined by the manifestation of at least two autoimmune endocrine diseases. Only few data exist on genetic associations of APS type 2. In this controlled study, 98 patients with APS type 2, 96 patients with type 1 diabetes (T1D), and 92 patients with autoimmune thyroid disease, both as a single autoimmune endocrinopathy, were tested for association with alleles of the human leukocyte antigen (HLA) class II loci DRB1, DQA1, and DQB1. Patients with APS type 2 had significantly more often the alleles DRB1*03 (P(c) < 0.0001), DRB1*04 (P(c) < 0.000005), DQA1*03 (P(c) < 0.0001), and DQB1*02 (P(c) < 0.05), when compared with controls. Less frequent…
Respiratory chain polymorphisms and obesity in the Spanish population, a cross-sectional study
2019
ObjectiveTo study the association of genes involved in the mitochondrial respiratory chain (MRC) pathway with body mass index (BMI) and obesity risk.DesignThis work studies three cross-sectional populations from Spain, representing three provinces: HORTEGA (Valladolid, Northwest/Centre), SEGOVIA (Segovia, Northwest/centre) and PIZARRA (Malaga,South).SettingForty-eight single nucleotide polymorphisms (SNPs) from MRC genes were selected and genotyped by SNPlex method. Association studies with BMI and obesity risk were performed for each population. These associations were then verified by analysis of the studied population as a whole (3731 samples).ParticipantsA total of 3731 Caucasian indivi…
A genome-wide association study of monozygotic twin-pairs suggests a locus related to variability of serum high-density lipoprotein cholesterol
2012
Serum lipid levels have been associated with cardiovascular diseases, metabolic syndrome and type II diabetes (Kannel et al., 1961; Miller & Miller, 1975; Pilia et al., 2006). Variation in lipids levels is highly influenced by heritable factors (Friedlander et al., 1997) and 95 loci have already been associated with levels of high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, triglycerides (TG) and total cholesterol (TC) in numerous study samples and replicated in various populations using genome-wide approaches (Aulchenko et al., 2008; Kathiresan et al., 2008; Kooner et al., 2008; Teslovich et al., 2010; Willer et al., 2008). However, the genetic associa…
Impact of the AHI1 gene on the vulnerability to schizophrenia: a case-control association study.
2010
Background: The Abelson helper integration-1 (AHI1) gene is required for both cerebellar and cortical development in humans. While the accelerated evolution of AHI1 in the human lineage indicates a role in cognitive (dys)function, a linkage scan in large pedigrees identified AHI1 as a positional candidate for schizophrenia. To further investigate the contribution of AHI1 to the susceptibility of schizophrenia, we evaluated the effect of AHI1 variation on the vulnerability to psychosis in two samples from Spain and Germany. Methodology/Principal Findings: 29 single-nucleotide polymorphisms (SNPs) located in a genomic region including the AHI1 gene were genotyped in two samples from Spain (28…
A polymorphism of the interleukin-1 receptor antagonist plays a prominent role within the interleukin-1 gene cluster in vulvar carcinogenesis
2003
Abstract Objective . The interleukin-1 (IL-1) family, that is, IL-1α and β and the IL-1 receptor antagonist (IL-1RA), is known to modulate various tumorgenic and tumorcidal effects in humans. Its biological function in squamous cell carcinogenesis of various anatomical sites has been stressed. Although various studies showed a certain association between genes encoding the IL-1 family and human malignancies, no data with respect to vulvar cancer have been published to date. Methods . We ascertained four polymorphisms of the IL-1α gene ( IL1A C[−889]T), the IL-1β gene ( IL1B promoter C[-511]T and IL1B exon 5 position +3953), and the IL-1RA gene ( IL1RN intron 2) in 68 patients with surgicall…
Spectrum of mutations and phenotypic expression in patients with autosomal dominant hypercholesterolemia identified in Italy.
2013
Abstract Objective To determine the spectrum of gene mutations and the genotype–phenotype correlations in patients with Autosomal Dominant Hypercholesterolemia (ADH) identified in Italy. Methods The resequencing of LDLR , PCSK9 genes and a selected region of APOB gene were conducted in 1018 index subjects clinically heterozygous ADH and in 52 patients clinically homozygous ADH. The analysis was also extended to 1008 family members of mutation positive subjects. Results Mutations were detected in 832 individuals: 97.4% with LDLR mutations, 2.2% with APOB mutations and 0.36% with PCSK9 mutations. Among the patients with homozygous ADH, 51 were carriers of LDLR mutations and one was an LDLR / …
Influence of gene action across different time scales on behavior.
2002
Genes can affect natural behavioral variation in different ways. Allelic variation causes alternative behavioral phenotypes, whereas changes in gene expression can influence the initiation of behavior at different ages. We show that the age-related transition by honey bees from hive work to foraging is associated with an increase in the expression of the foraging ( for ) gene, which encodes a guanosine 3′,5′-monophosphate (cGMP)–dependent protein kinase (PKG). cGMP treatment elevated PKG activity and caused foraging behavior. Previous research showed that allelic differences in PKG expression result in two Drosophila foraging variants. The same gene can thus exert different types of influe…
Major histocompatibility complex and sporadic Alzheimer's disease: a critical reappraisal
2003
Epidemiological data suggest that some genetic determinants of Alzheimer's disease (AD) might reside in those polymorphisms for the immune system genes that regulate immune inflammatory responses, such as the major histocompatibility complex (MHC). Therefore, MHC polymorphisms have been the focus of a large number of AD association studies. Class Ia, Ib (hemochromatosis gene (HFE)), class II and class III (complement, tumour necrosis factor and heat shock proteins) alleles have been studied. Nearly every positive result has been followed by several studies that have failed to replicate it or that have contradicted it. Several factors, including methodological biases, might explain these dis…