Coding SNP (coding + snp)

Distribution by Scientific Domains


Selected Abstracts


Association of a single nucleotide polymorphism in neuronal acetylcholine receptor subunit alpha 5 (CHRNA5) with smoking status and with ,pleasurable buzz' during early experimentation with smoking

ADDICTION, Issue 9 2008
Richard Sherva
ABSTRACT Aims To extend the previously identified association between a single nucleotide polymorphism (SNP) in neuronal acetylcholine receptor subunit alpha-5 (CHRNA5) and nicotine dependence to current smoking and initial smoking-experience phenotypes. Design, setting, participants Case,control association study with a community-based sample, comprising 363 Caucasians and 72 African Americans (203 cases, 232 controls). Measurements Cases had smoked , five cigarettes/day for , 5 years and had smoked at their current rate for the past 6 months. Controls had smoked between one and 100 cigarettes in their life-time, but never regularly. Participants also rated, retrospectively, pleasurable and displeasurable sensations experienced when they first smoked. We tested for associations between smoking phenotypes and the top 25 SNPs tested for association with nicotine dependence in a previous study. Findings A non-synonymous coding SNP in CHRNA5, rs16969968, was associated with case status [odds ratio (OR) = 1.5, P = 0.01] and, in Caucasians, with experiencing a pleasurable rush or buzz during the first cigarette (OR = 1.6, P = 0.01); these sensations were associated highly with current smoking (OR = 8.2, P = 0.0001). Conclusions We replicated the observation that the minor allele of rs16969968 affects smoking behavior, and extended these findings to sensitivity to smoking effects upon experimentation. While the ability to test genetic associations was limited by sample size, the polymorphism in the CHRNA5 subunit was shown to be associated significantly with enhanced pleasurable responses to initial cigarettes in regular smokers in an a priori test. The findings suggest that phenotypes related to subjective experiences upon smoking experimentation may mediate the development of nicotine dependence. [source]


Autism-like behavioral phenotypes in BTBR T+tf/J mice

GENES, BRAIN AND BEHAVIOR, Issue 2 2008
H. G. McFarlane
Autism is a behaviorally defined neurodevelopmental disorder of unknown etiology. Mouse models with face validity to the core symptoms offer an experimental approach to test hypotheses about the causes of autism and translational tools to evaluate potential treatments. We discovered that the inbred mouse strain BTBR T+tf/J (BTBR) incorporates multiple behavioral phenotypes relevant to all three diagnostic symptoms of autism. BTBR displayed selectively reduced social approach, low reciprocal social interactions and impaired juvenile play, as compared with C57BL/6J (B6) controls. Impaired social transmission of food preference in BTBR suggests communication deficits. Repetitive behaviors appeared as high levels of self-grooming by juvenile and adult BTBR mice. Comprehensive analyses of procedural abilities confirmed that social recognition and olfactory abilities were normal in BTBR, with no evidence for high anxiety-like traits or motor impairments, supporting an interpretation of highly specific social deficits. Database comparisons between BTBR and B6 on 124 putative autism candidate genes showed several interesting single nucleotide polymorphisms (SNPs) in the BTBR genetic background, including a nonsynonymous coding region polymorphism in Kmo. The Kmo gene encodes kynurenine 3-hydroxylase, an enzyme-regulating metabolism of kynurenic acid, a glutamate antagonist with neuroprotective actions. Sequencing confirmed this coding SNP in Kmo, supporting further investigation into the contribution of this polymorphism to autism-like behavioral phenotypes. Robust and selective social deficits, repetitive self-grooming, genetic stability and commercial availability of the BTBR inbred strain encourage its use as a research tool to search for background genes relevant to the etiology of autism, and to explore therapeutics to treat the core symptoms. [source]


Association of Molecular Variants, Haplotypes, and Linkage Disequilibrium Within the Human Vitamin D-Binding Protein (DBP) Gene With Postmenopausal Bone Mineral Density,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2003
Yoichi Ezura
Abstract Possible contribution of vitamin D-binding protein (DBP) gene for determination of BMD was tested by characterizing 13 SNPs in 384 adult Japanese women. When the effect of a specific single SNP was tested, five SNPs (,39C>T, IVS1+827C>T, IVS1+1916C>T, IVS1-1154A>G, and IVS11+1097G>C) correlated with BMD significantly at various levels. The chromosomal dosage of one haplotype (T-C-C-G-T-C in ,39C>T, IVS1+827C>T, IVS1+1916C>T, IVS1-1154A>G, D432E, and IVS11+1097G>C) displayed significant correlation with adjusted radial BMD (r = 0.15, p = 0.008; n = 331). Multiple regression analyses revealed a most significant correlation with the combination of IVS1+827C>T and D432E (r2 = 0.029, p = 0.005). These results indicate a complex combined effect of several SNPs within the DBP gene that might underlie susceptibility to low radial BMD and osteoporosis. Introduction: Osteoporosis results from the interplay of multiple environmental and genetic determinants. The gene encoding vitamin D-binding protein (DBP), a key factor for regulating calcium homeostasis through the vitamin D endocrine system, is a probable candidate for conferring susceptibility to osteoporosis. Methods: To test a possible contribution of the DBP gene for determination of bone mineral density (BMD) of adult women, we have characterized 13 single nucleotide polymorphisms (SNPs) within the DBP gene in DNA from 384 adult Japanese women and attempted to correlate specific SNPs with BMD. Results and Conclusions: Sixteen major haplotypes accounted for 80% of the variations, indicating allelic complexity in this genomic region. Pairwise linkage disequilibrium (LD), measured by the D, and r2 statistics, demonstrated a general pattern of decline with increasing distance, but individual LD values within small genomic segments were diverse. Regression analysis for adjusted BMD revealed significant correlation with respect to five of them (,39C>T, IVS1+827C>T, IVS1+1916C>T, IVS1-1154A>G, and IVS11+1097G>C) at various levels. An intronic SNP (IVS11+1097G>C) with the highest significance of association (p = 0.006) showed significant LD with four SNPs located around the first exon (r2 values >0.18, D, > 0.5). A non-synonymous coding SNP, D432E, showed a comparable level of correlation, but it was in a moderate LD only with IVS11+1097G>C. The chromosomal dosage of one haplotype (T-C-C-G-T-C in ,39C>T, IVS1+827C>T, IVS1+1916C>T, IVS1-1154A>G, D432E and IVS11+1097G>C) estimated in each subject displayed significant correlation with adjusted radial BMD (r = 0.15, p = 0.008; n = 331). Furthermore, multiple regression analyses revealed that the most significant correlation was achieved for the combination of IVS1+827C>T and D432E (r2 = 0.029, p = 0.005). These results indicate a complex combined effect of several SNPs within the DBP gene that might underlie susceptibility to low radial BMD and osteoporosis. [source]


Associations and Interactions Between SNPs in the Alcohol Metabolizing Genes and Alcoholism Phenotypes in European Americans

ALCOHOLISM, Issue 5 2009
Richard Sherva
Background:, Alcohol dependence is a major cause of morbidity and mortality worldwide and has a strong familial component. Several linkage and association studies have identified chromosomal regions and/or genes that affect alcohol consumption, notably in genes involved in the 2-stage pathway of alcohol metabolism. Methods:, Here, we use multiple regression models to test for associations and interactions between 2 alcohol-related phenotypes and SNPs in 17 genes involved in alcohol metabolism in a sample of 1,588 European American subjects. Results:, The strongest evidence for association after correcting for multiple testing was between rs1229984, a nonsynonymous coding SNP in ADH1B, and DSM-IV symptom count (p = 0.0003). This SNP was also associated with maximum number of drinks in 24 hours (p = 0.0004). Each minor allele at this SNP predicts 45% fewer DSM-IV symptoms and 18% fewer max drinks. Another SNP in a splice site in ALDH1A1 (rs8187974) showed evidence for association with both phenotypes as well (p = 0.02 and 0.004, respectively), but neither association was significant after accounting for multiple testing. Minor alleles at this SNP predict greater alcohol consumption. In addition, pairwise interactions were observed between SNPs in several genes (p = 0.00002). Conclusions:, We replicated the large effect of rs1229984 on alcohol behavior, and although not common (MAF = 4%), this polymorphism may be highly relevant from a public health perspective in European Americans. Another SNP, rs8187974, may also affect alcohol behavior but requires replication. Also, interactions between polymorphisms in genes involved in alcohol metabolism are likely determinants of the parameters that ultimately affect alcohol consumption. [source]