Gene‐Gene Interaction Among WNT Genes for Oral Cleft in Trios

Genome‐wide association studies (GWAS) for nonsyndromic cleft lip with or without cleft palate (CL/P) have identified multiple genes as important in the etiology of this common birth defect. We performed a candidate gene/pathway analysis explicitly considering gene‐gene (G × G) interaction to further explore the etiology of CL/P. Animal models have shown the WNT signaling pathway plays an important role in mid‐facial development, and various genes in this pathway have been associated with nonsyndromic CL/P in previous studies. We propose a combined approach to search for possible G × G interactions using machine learning and regression‐based methods to test for interactions between genes in the WNT family, and between these genes and other genes identified by GWAS in case‐parent trios. Using this combined approach of regression‐based and machine learning methods in CL/P case‐parent trios, we found robust evidence of G × G interaction between markers in WNT5B and MAFB (empiric P‐values = 0.0076 among Asian trios and P‐values = 0.018 among European trios). Additional evidence for epistatic interaction between markers in WNT5A, IRF6, and C1orf107 was seen among Asian trios, and markers in the 8q24 region and WNT5B among European trios.     

中国人群WNT代谢通路与非综合征型唇腭裂的亲源效应分析

目的 非综合征型唇裂合并或不合并腭裂（NSCL/P）是一类常见的出生缺陷,遗传致病因素一直是其病因学研究的热点。本研究拟基于家系设计在WNT代谢通路基因中探索亲源效应对NSCL/P发病风险的影响。方法 本研究人群为“唇腭裂的基因组学国际合作组研究”项目在中国地区募集的806个NSCL/P核心家系。利用对数线性模型探索WNT基因及其单体型的亲源效应与疾病的关联,采用Wald检验探索亲源效应与环境因素的交互作用。经过Bonferroni多重检验校正后,统计学检验的显著性阈值设为P<3.47×10^-4。结果 质量控制后共纳入7个基因上144个单核苷酸多态性位点进行分析。结果显示,NSCL/P家系中有8个位点具有潜在的亲源效应（P<0.05）,但经Bonferroni多重检验校正后,均未达到统计学显著性水平（P>3.47×10^-4）。NSCL/P家系中位于WNT9A rs4074668-rs12725747单体型（T-A）具有亲源效应,且经Bonferroni校正后差异仍有统计学意义（P=2.74×10^-4）。但该单体型的亲源效应与环境因素（被动吸烟、复合维生素补充）的交互作用并未达到统计学显著水平。结论 WNT代谢通路基因可能通过亲源效应影响NSCL/P的发生风险。位于WNT9A基因rs4074668-rs12725747单体型（T-A）亲源效应与NSCL/P发病风险存在显著关联。未来仍需其他独立样本验证以进一步确认WNT代谢通路在NSCL/P发生中的作用。     

Multipoint linkage disequilibrium mapping for complex diseases

Linkage disequilibrium (LD) or association studies using case-parent trios have become a common approach to locate unobserved susceptibility genes underlying complex diseases. With the availability of ever more dense marker maps, how to utilize the information carried by multiple markers simultaneously remains challenging. Recently, Liang et al. ([2001a] Am. J. Hum. Genet. 68: 937-950) proposed a multipoint LD method to estimate the location of a susceptibility gene within a framework map along with its sampling uncertainty. Two important features of this method are that 1) it uses all trios whether parents are heterozygous for a given marker or not, and 2) it provides a single test statistic for the null hypothesis of no linkage or no LD to the region, avoiding the multiple testing problem encountered when performing individual transmission disequilibrium tests (TDT) for each marker individually. In this paper, we discuss how this method can be expanded to address important issues pertaining to complex diseases in a unified fashion. These issues include, among others, gene-gene and gene-environment interactions, genetic heterogeneity, phenotypic refinement, and paternal vs. maternal transmission. We applied this method to asthmatic case-parent trios from the Collaborative Study on the Genetics of Asthma (CSGA), and found that the previous evidence for linkage and LD in a 13.6 cM region of chromosome 11 can be attributed to maternal transmission, while there was no evidence of excess paternal transmission. Furthermore, such discrepancy in preferential transmission was most evident among probands with early onset age (6 years old or younger).     

Testing candidate genes for non-syndromic oral clefts using a case-parent trio design.

Markers in five candidate genes were examined on 269 case-parent trios ascertained through a child with an isolated, non-syndromic oral cleft (cleft lip, CL; cleft palate, CP; or cleft lip and palate, CLP). Cases and their parents were ascertained through treatment centers in Maryland. Markers at two of the five candidate genes, transforming growth factor beta3 (TGFbeta3) and MSX1, showed consistent evidence of linkage and disequilibrium due to linkage using several statistical tests (e.g., the global chi-square for TGFbeta3 was 21.1 with 12 df, P = 0.03; that for MSX1 was 8.7 with 3 df, P = 0.03). There was little evidence of heterogeneity in the role of TGFbeta3 between different types of oral clefts, but MSX1 did yield marginal evidence for such heterogeneity. MSX1 also showed evidence for interaction between infant's genotype and maternal smoking, giving a likelihood ratio test for heterogeneity between smoker and non-smoker mothers of 7.16 (2 df, P = 0.03). Using a conditional logistic model to test for gene-gene interaction showed no evidence of interaction between TGFbeta3 and MSX1, with both seeming to contribute independently to risk of isolated, non-syndromic oral clefts.     

Genetic variants in IRF6 and the risk of facial clefts: single-marker and haplotype-based analyses in a population-based case-control study of facial clefts in Norway

Mutations in the gene encoding interferon regulatory factor 6 (IRF6) underlie a common form of syndromic clefting known as Van der Woude syndrome. Lip pits and missing teeth are the only additional features distinguishing the syndrome from isolated clefts. Van der Woude syndrome, therefore, provides an excellent model for studying the isolated forms of clefting. From a population-based case-control study of facial clefts in Norway (1996-2001), we selected 377 cleft lip with or without cleft palate (CL/P), 196 cleft palate only (CPO), and 763 control infant-parent triads for analysis. We genotyped six single nucleotide polymorphisms within the IRF6 locus and estimated the relative risks (RR) conferred on the child by alleles and haplotypes of the child and of the mother. On the whole, there were strong statistical associations with CL/P but not CPO in our data. In single-marker analyses, mothers with a double-dose of the 'a'-allele at rs4844880 had an increased risk of having a child with CL/P (RR=1.85, 95% confidence interval: 1.04-3.25; P=0.036). An RR of 0.38 (95% confidence interval: 0.16-0.92; P=0.031) was obtained when the child carried a single-dose of the 'a'-allele at rs2235371 (the p.V274I polymorphism). The P-value for the overall test was <0.001. In haplotype analyses, several of the fetal and maternal haplotype relative risks were statistically significant individually but were not strong enough to show up on the overall test (P=0.113). Taken together, these findings further support a role for IRF6 variants in clefting of the lip and provide specific risk estimates in a Norwegian population.     

Evidence for SNP‐SNP interaction identified through targeted sequencing of cleft case‐parent trios

Nonsyndromic cleft lip with or without cleft palate (NSCL/P) is the most common craniofacial birth defect in humans, affecting 1 in 700 live births. This malformation has a complex etiology where multiple genes and several environmental factors influence risk. At least a dozen different genes have been confirmed to be associated with risk of NSCL/P in previous studies. However, all the known genetic risk factors cannot fully explain the observed heritability of NSCL/P, and several authors have suggested gene‐gene (G × G) interaction may be important in the etiology of this complex and heterogeneous malformation. We tested for G × G interactions using common single nucleotide polymorphic (SNP) markers from targeted sequencing in 13 regions identified by previous studies spanning 6.3 Mb of the genome in a study of 1,498 NSCL/P case‐parent trios. We used the R‐package trio to assess interactions between polymorphic markers in different genes, using a 1 degree of freedom (1df) test for screening, and a 4 degree of freedom (4df) test to assess statistical significance of epistatic interactions. To adjust for multiple comparisons, we performed permutation tests. The most significant interaction was observed between rs6029315 in MAFB and rs6681355 in IRF6 (4df P = 3.8 × 10^?8) in case‐parent trios of European ancestry, which remained significant after correcting for multiple comparisons. However, no significant interaction was detected in trios of Asian ancestry.     

Examining markers in 8q24 to explain differences in evidence for association with cleft lip with/without cleft palate between Asians and Europeans

In a recent genome-wide association study (GWAS) from an international consortium, evidence of linkage and association in chr8q24 was much stronger among nonsyndromic cleft lip/palate (CL/P) case-parent trios of European ancestry than among trios of Asian ancestry. We examined marker information content and haplotype diversity across 13 recruitment sites (from Europe, United States, and Asia) separately, and conducted principal components analysis (PCA) on parents. As expected, PCA revealed large genetic distances between Europeans and Asians, and a north-south cline from Korea to Singapore in Asia, with Filipino parents forming a somewhat distinct Southeast Asian cluster. Hierarchical clustering of SNP heterozygosity revealed two major clades consistent with PCA results. All genotyped SNPs giving P < 10(-6) in the allelic transmission disequilibrium test (TDT) showed higher heterozygosity in Europeans than Asians. On average, European ancestry parents had higher haplotype diversity than Asians. Imputing additional variants across chr8q24 increased the strength of statistical evidence among Europeans and also revealed a significant signal among Asians (although it did not reach genome-wide significance). Tests for SNP-population interaction were negative, indicating the lack of strong signal for 8q24 in families of Asian ancestry was not due to any distinct genetic effect, but could simply reflect low power due to lower allele frequencies in Asians.     

Investigation of the candidate genes ACTHR and Golf for bipolar illness by the transmission/disequilibrium test

Several versions of the transmission/disequilibrium test (TDT) were applied to the two candidate genes ACTHR and Golf for bipolar illness. Analyses were carried out separately for paternal and maternal transmission. Evidence for linkage and association was found for ACTHR for paternal transmission in support of a parent-of-origin effect. Possible evidence for segregation distortion was found for one of the two markers for Golf for maternal transmission. © 1997 Wiley-Liss, Inc.     

IMMP2L和DOCK4基因多态性与中国汉族儿童孤独症的关联研究

目的 探讨IMMP2L和DOCK4基因多态性与中国汉族儿童孤独症的关联性。方法 收集375个中国汉族人群的孤独症核心家系, 所有家系均采集外周血提取基因组DNA, 采用SNaPshot基因分型的方法, 检测IMMP2L基因rs12537269、rs1528039及DOCK4基因rs2217262位点的等位基因和基因型分布, 通过传递不平衡检验(Transmission/disequilibrium test, TDT)分析所研究位点多态性与孤独症的关系。结果 TDT结果显示, rs12537269和rs1528039位点在杂合子父母的2个不同等位基因之间无优势传递(P>0.05), 而rs2217262位点杂合子父母过多的传递A给患儿(χ²=5.343, P=0.021), 发生传递不平衡。结论 DOCK4基因与中国汉族儿童孤独症存在关联性。     

Exploring the effects of methylenetetrahydrofolate reductase gene variants C677T and A1298C on the risk of orofacial clefts in 261 Norwegian case-parent triads

Folic acid and the methylenetetrahydrofolate reductase (MTHFR) gene have both been implicated in the etiology of orofacial clefts. The authors selected 261 case-parent triads (173 cases with cleft lip with or without cleft palate (CL/P) and 88 cases with cleft palate only (CPO)) from a Norwegian population-based study of orofacial clefts (May 1996-1998). A case-parent triad design was used to examine whether MTHFR variants C677T and A1298C, and their haplotypes, are risk factors for orofacial clefts. Among CL/P cases, the child's genotype at C677T or A1298C did not influence the risk. However, children of mothers carrying the C677T variant allele had a lower risk of CL/P. For CPO, children carrying the C677T variant allele had about a twofold increased risk, whereas the mother's genotypes did not contribute to the risk. The haplotype-based transmission/disequilibrium test showed that except for 677T/1298A (p = 0.06), none of the other haplotypes showed evidence of excess transmission to the offspring. The authors also explored interaction of C677T with maternal use of folic acid among children with CPO. Surprisingly, the risk associated with the child's carrying either CT or TT was higher (fourfold) when the mother used folic acid. These findings suggest a possible role of MTHFR and folic acid in the causation of orofacial clefts, but the strength and direction of these effects remain to be clarified.     

Wound healing genes and susceptibility to cutaneous leishmaniasis in Brazil

Leishmania braziliensis causes cutaneous (CL) and mucosal (ML) leishmaniasis. In the mouse, Fli1 was identified as a gene influencing enhanced wound healing and resistance to CL caused by Leishmania major. Polymorphism at FLI1 is associated with CL caused by L. braziliensis in humans, with an inverse association observed for ML disease. Here we extend the analysis to look at other wound healing genes, including CTGF, TGFB1, TGFBR1/2, SMADS 2/3/4/7 and FLII, all functionally linked along with FLI1 in the TGF beta pathway. Haplotype tagging single nucleotide polymorphisms (tag-SNPs) were genotyped using Taqman technology in 325 nuclear families (652 CL cases; 126 ML cases) from Brazil. Robust case-pseudocontrol (CPC) conditional logistic regression analysis showed associations between CL and SNPs at CTGF (SNP rs6918698; CC genotype; OR 1.67; 95%CI 1.10-2.54; P=0.016), TGFBR2 (rs1962859; OR 1.50; 95%CI 1.12-1.99; P=0.005), SMAD2 (rs1792658; OR 1.57; 95%CI 1.04-2.38; P=0.03), SMAD7 (rs4464148; AA genotype; OR 2.80; 95%CI 1.00-7.87; P=0.05) and FLII (rs2071242; OR 1.60; 95%CI 1.14-2.24; P=0.005), and between ML and SNPs at SMAD3 (rs1465841; OR 2.15; 95%CI 1.13-4.07; P=0.018) and SMAD7 (rs2337107; TT genotype; OR 3.70; 95%CI 1.27-10.7; P=0.016). Stepwise logistic regression analysis showed that all SNPs associated with CL at FLI1, CTGF, TGFBR2, and FLII showed independent effects from each other, but SNPs at SMAD2 and SMAD7 did not add independent effects to SNPs from other genes. These results suggest that TGFβ signalling via SMAD2 is important in directing events that contribute to CL, whereas signalling via SMAD3 is important in ML. Both are modulated by the inhibitory SMAD7 that acts upstream of SMAD2 and SMAD3 in this signalling pathway. Along with the published FLI1 association, these data further contribute to the hypothesis that wound healing processes are important determinants of pathology associated with cutaneous forms of leishmaniasis.     

Quantitative trait association in parent offspring trios: Extension of case/pseudocontrol method and comparison of prospective and retrospective approaches

The case/pseudocontrol method provides a convenient framework for family-based association analysis of case-parent trios, incorporating several previously proposed methods such as the transmission/disequilibrium test and log-linear modelling of parent-of-origin effects. The method allows genotype and haplotype analysis at an arbitrary number of linked and unlinked multiallelic loci, as well as modelling of more complex effects such as epistasis, parent-of-origin effects, maternal genotype and mother-child interaction effects, and gene-environment interactions. Here we extend the method for analysis of quantitative as opposed to dichotomous (e.g. disease) traits. The resulting method can be thought of as a retrospective approach, modelling genotype given trait value, in contrast to prospective approaches that model trait given genotype. Through simulations and analytical derivations, we examine the power and properties of our proposed approach, and compare it to several previously proposed single-locus methods for quantitative trait association analysis. We investigate the performance of the different methods when extended to allow analysis of haplotype, maternal genotype and parent-of-origin effects. With randomly ascertained families, with or without population stratification, the prospective approach (modeling trait value given genotype) is found to be generally most effective, although the retrospective approach has some advantages with regard to estimation and interpretability of parameter estimates when applied to selected samples.     

Oral facial clefts and gene polymorphisms in metabolism of folate/one‐carbon and vitamin A: a pathway‐wide association study

An increased risk of facial clefts has been observed among mothers with lower intake of folic acid or vitamin A around conception. We hypothesized that the risk of clefts may be further moderated by genes involved in metabolizing folate or vitamin A. We included 425 case‐parent triads in which the child had either cleft lip with or without cleft palate (CL/P) or cleft palate only (CPO), and no other major defects. We analyzed 108 SNPs and one insertion in 29 genes involved in folate/one‐carbon metabolism and 68 SNPs from 16 genes involved in vitamin A metabolism. Using the Triad Multi‐Marker (TRIMM) approach we performed SNP, gene, chromosomal region, and pathway‐wide association tests of child or maternal genetic effects for both CL/P and CPO. We stratified these analyses on maternal intake of folic acid or vitamin A during the periconceptional period. As expected with this high number of statistical tests, there were many associations with P‐values<0.05; although there were fewer than predicted by chance alone. The strongest association in our data (between fetal FOLH1 and CPO, P=0.0008) is not in agreement with epidemiologic evidence that folic acid reduces the risk of CL/P in these data, not CPO. Despite strong evidence for genetic causes of oral facial clefts and the protective effects of maternal vitamins, we found no convincing indication that polymorphisms in these vitamin metabolism genes play an etiologic role. Genet. Epidemiol. 2009. © 2008 Wiley Liss, Inc.     

Evidence for gene-environment interaction in a genome wide study of nonsyndromic cleft palate

Nonsyndromic cleft palate (CP) is a common birth defect with a complex and heterogeneous etiology involving both genetic and environmental risk factors. We conducted a genome-wide association study (GWAS) using 550 case-parent trios, ascertained through a CP case collected in an international consortium. Family-based association tests of single nucleotide polymorphisms (SNP) and three common maternal exposures (maternal smoking, alcohol consumption, and multivitamin supplementation) were used in a combined 2 df test for gene (G) and gene-environment (G × E) interaction simultaneously, plus a separate 1 df test for G × E interaction alone. Conditional logistic regression models were used to estimate effects on risk to exposed and unexposed children. While no SNP achieved genome-wide significance when considered alone, markers in several genes attained or approached genome-wide significance when G × E interaction was included. Among these, MLLT3 and SMC2 on chromosome 9 showed multiple SNPs resulting in an increased risk if the mother consumed alcohol during the peri-conceptual period (3 months prior to conception through the first trimester). TBK1 on chr. 12 and ZNF236 on chr. 18 showed multiple SNPs associated with higher risk of CP in the presence of maternal smoking. Additional evidence of reduced risk due to G × E interaction in the presence of multivitamin supplementation was observed for SNPs in BAALC on chr. 8. These results emphasize the need to consider G × E interaction when searching for genes influencing risk to complex and heterogeneous disorders, such as nonsyndromic CP.     

Genetic epidemiology of cleft lip with or without cleft palate in the population of Hawaii

Orientals consisting of Japanese, Chinese, Koreans, and Filipinos are clearly at higher risk for cleft lip with or without cleft palate [CL(P)] than whites, Puerto Ricans, and Hawaiians/part-Hawaiians in Hawaii. Using the model of diallele cross, CL(P) incidences in incrosses and outcrosses involving 564,002 live births distributed among 669 mating types were analyzed to study the extent of major gene involvement in the difference in the two groups and to investigate maternal effect in the etiology of CL(P). CL(P) cases excluding syndrome cases were classified into two types: all CL(P) cases and CL(P) cases without additional malformations. For either type there was no evidence to suggest that simple major gene plays a dominant role in accounting for racial differences as measured by deviations from additivity in the hybrids. For CL(P) cases without additional defects, a negative "maternal effect" was detected in Filipinos such that higher risk for this racial group depends on when the father is Filipino. Implications of the findings are discussed.     

Does the interaction between maternal folate intake and the methylenetetrahydrofolate reductase polymorphisms affect the risk of cleft lip with or without cleft palate?

Periconceptional folic acid supplementation may reduce the risk of cleft lip with or without cleft palate (CL(P)). Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene reduce availability of 5-methyltetrahydrofolate, the predominant circulating form of folate. To determine the effect of MTHFR C677T and MTHFR A1298C genotypes and haplotypes on CL(P) risk and the interaction with maternal periconceptional dietary folate and folic acid supplement intake, the authors conducted a case-control triad study in the Netherlands (1998-2000) among 179 CL(P) and 204 control families. Infant and parental MTHFR C677T and MTHFR A1298C genotypes and haplotypes were not associated with CL(P) risk in the case-control and transmission disequilibrium test analyses. Mothers carrying the MTHFR 677TT genotype and who either did not use folic acid supplements periconceptionally or had a low dietary folate intake, or both, had an increased risk of delivering a CL(P) child (odds ratio (OR) = 5.9, 95% confidence interval (CI): 1.1, 30.9; OR = 2.8, 95% CI: 0.7, 10.5; OR = 10.0, 95% CI: 1.3, 79.1, respectively). No supplement use, low dietary folate intake, and maternal MTHFR 1298CC genotype increased the risk of CL(P) offspring almost sevenfold (OR = 6.5, 95% CI: 1.4, 30.2). Thus, the detrimental effect of low periconceptional folate intake on the risk of giving birth to a CL(P) child was more pronounced in mothers with the MTHFR 677TT or MTHFR 1298CC genotype.     

TSC1、TSC2基因多态性和儿童孤独症的家系研究

目的 探讨结节性硬化症(tuberous sclerosis complex,TSC)相关基因TSC1、TSC2基因多态性与儿童孤独症之间的关联。 方法 利用SNaPshot基因分型技术,在97例孤独症核心家系中,对TSC1、TSC2基因上的8个标签SNP,即rs3761840、rs2809244、rs1050700、rs739441、rs2074968、rs2074969、rs2072314、rs8063461进行分型;通过FBAT软件及Haploview软件进行基于家系的单倍型分析。 结果 1)基于家系的关联分析发现8个SNPs等位基因中有2个SNPs的等位基因倾向于过传递(rs1050700 A:Z=2.708,P=0.006769;rs2074968 G:Z=3.244,P=0.001180),并且经过FDR校正后,2个SNPs仍显示出与孤独症之间存在显著关联性(校正P值分别为0.027,0.014)。2)rs3761840-rs2809244基因型的单体型A-C显示出显著的传递不平衡,双亲较少传递给子女(Z=-2.297,P=0.021629)。rs2074968-rs2072314基因型的2种单体型即 G-C及C-C均显示出显著的传递不平衡,单体型G-C能从双亲过传递给子女(Z=2.596,P=0.009444),单体型C-C则相反(Z=-3.657,P=0.000256)。 结论 TSC1、TSC2基因可能与儿童孤独症的发生存在关联。     

Identification of 16q21 as a modifier of nonsyndromic orofacial cleft phenotypes

Orofacial clefts (OFCs) are common, complex birth defects with extremely heterogeneous phenotypic presentations. Two common subtypes—cleft lip alone (CL) and CL plus cleft palate (CLP)—are typically grouped into a single phenotype for genetic analysis (i.e., CL with or without cleft palate, CL/P). However, mounting evidence suggests there may be unique underlying pathophysiology and/or genetic modifiers influencing expression of these two phenotypes. To this end, we performed a genome‐wide scan for genetic modifiers by directly comparing 450 CL cases with 1,692 CLP cases from 18 recruitment sites across 13 countries from North America, Central or South America, Asia, Europe, and Africa. We identified a region on 16q21 that is strongly associated with different cleft type (P  = 5.611 × 10^?8). We also identified significant evidence of gene–gene interactions between this modifier locus and two recognized CL/P risk loci: 8q21 and 9q22 (FOXE1 ) (P  = 0.012 and 0.023, respectively). Single nucleotide polymorphism (SNPs) in the 16q21 modifier locus demonstrated significant association with CL over CLP. The marker alleles on 16q21 that increased risk for CL were found at highest frequencies among individuals with a family history of CL (P  = 0.003). Our results demonstrate the existence of modifiers for which type of OFC develops and suggest plausible elements responsible for phenotypic heterogeneity, further elucidating the complex genetic architecture of OFCs.     

NLGN4X基因3'UTR区多态性与孤独症关系的家系研究

【目的】 探讨NLGN4X基因与中国汉族儿童孤独症是否存在相关性,查寻中国汉族儿童孤独症的易感基因。 【方法】 选取NLGN4X基因3'UTR区两个多态性位点rs5916269和rs3810686作为遗传标记,采用直接测序法对92个孤独症核心家系的276名成员进行基因型测定,并进行传递不平衡检验(TDT)和单倍型相对危险度(HRR)分析。 【结果】 TDT检验及HRR分析均显示儿童孤独症与rs5916269遗传标记位点不存在传递不平衡(TDT χ²=0.385,P=0.620;HRR χ²=0.345,P=0.557);与rs3810686遗传标记位点存在传递不平衡(TDT χ²=6.368,P=0.015;HRR χ²=5.470,P=0.019)。 【结论】 NLGN4X基因rs5916269位点与中国汉族儿童孤独症无关;rs3810686位点与中国汉族儿童孤独症相关,NLGN4X基因可能是孤独症的易感基因。     

胞浆型磷脂酶A2家族基因多态性与精神分裂症的关联性研究

目的 探讨中国北方汉族人群胞浆型磷脂酶A2(cPLA2)家族基因多态性与精神分裂症的遗传关联性.方法 采用聚合酶链反应(PCR)和连接酶检测反应(LDR)方法,在201个精神分裂症患者核心家系中检测cPLA2家族基因上的10个单核苷酸多态性(SNPs),对结果进行单倍型相对风险分析(HRR)、传递不平衡分析(TDT)、单倍型分析和多位点联合分析.结果 各位点在精神分裂症病例组和对照组中基因型分布均符合Hardy-Weinberg平衡.HRR和TDT分析表明,检测的10个SNPs位点与精神分裂症无关联性(P＞0.05).单倍型分析结果显示,由同一染色体上各位点组成的单倍型与精神分裂症均无关联性(P＞0.05).多位点联合作用分析显示,rs2162886与rsl668589,rs891014与rsl668589,rs2307279与rs7542180位点的联合作用与精神分裂症相关联(χ²=6.913,P=0.032;χ²=8.393,P=0.015;χ²=8.447,P=0.038).结论 cPLA2家族基因中存在多个与精神分裂症关联的易感位点.