Family-Based Association Study Of FTSJ1 With Mental Retardation Of The Population In Qinba Mountain Region

Mental retardation is a complex disorder characterized by functional deficience of the central nervous system resulting in 'significant subnomality both in intellectual functioning and in adaptive behavior,' originating before 18 years of age.Mental retardation is one of the most considerable unresolved problems.The Qinba mountain region is one of the higher MR prevalence areas in China.For the purpose of preventing and curing MR in this region,we should do further study to make sure the genetic pathogeny of MR in Qinba region.FTSJ1 is an MR morbigenous gene identified recently.The function of FTSJ1 in human is yet unknown,FTSJ1 may plays an essential role in translation process of protein synthesis, tRNA processing,rRNA processing and RNA methylation.The result of association studies on FTSJ1 gene with MR shows that most mutations in the gene are single site mutations.A case-control study did by Dai Ling and others supports FTSJ1 gene has a positive association with NS-XLMR in young males in Qinba mountain region in China.In their study both the single polymorphism and individual haplotypes showed significant association with MR.Our study use family-based association,which could avoid spurious results caused by population stratification.We selected three SNPs(rs2268954,rs2070991,rs5905692) and performed a Transmission Disequilibrium Test(TDT) in 77 Chinese Han trios Qinba mountain to investigate the association of FTSJ1 gene with MR family group population in this region.In this study we used the PCR-SSCP method to do the genotyping assay.Our results suggested neither single marker nor haplotype is associated with MR,which didn't support that the three SNPs selected in this study were susceptible sites in China Han population in Qinba mountain region in FTSJ1 gene.And the negative result could not preclude mutations causing MR nearby.Our result may also simply reflect the problems of complex diseases on genetics.We should avoid the population stratification by environmental factors,enlarge the sum total of sample,and improve our research methods.It is more mesningful to do further studies of the role of FTSJ1 gene playing on MR group in Qinba mountain region.