OBJECTIVEConvincing evidence suggests a link between increased risk of nonsyndromic cleft lip with or without cleft palate (NSCL/P) and low intake of folic acid by the mother during pregnancy. The present study was designed to explore if genetic variation in the betaine-homocysteine methyltransferase (BHMT) gene contributes to NSCL/P.

METHODSDNA was obtained from 166 individuals with NSCL/P and 285 healthy subjects. Three known single nucleotide polymorphisms (SNPs) present in the BHMT gene (rs651852, rs3797546, and rs3733890) were investigated by real-time PCR-based TaqMan genotyping.

RESULTSNeither allelic nor genotypic association was found between NSCL/P and SNPs rs651852 and rs3733890. SNP rs3797546 did not show allelic association with NSCL/P; however, a higher proportion of NSCL/P patients carry the CC genotype compared with the TT+CT genotype (P=0.020, OR=2.10, 95% CI=1.11-3.95).

CONCLUSIONOur study suggests that polymorphism rs3797546 in the BHMT gene may confer genetic risk of NSCL/P in a recessive manner.

Asian Continental Ancestry Group ; genetics ; Betaine-Homocysteine S-Methyltransferase ; genetics ; metabolism ; Case-Control Studies ; China ; Cleft Lip ; genetics ; Cleft Palate ; genetics ; Gene Expression Regulation ; Genetic Predisposition to Disease ; Genotype ; Humans ; Polymorphism, Single Nucleotide ; Risk Factors

Objective:In order to investigate the genetic diversity of mitochondrial cytochrome b (Cytb) gene of Taenia asiatica ( T. asiatica) in Dali Bai Autonomous Prefecture (Dali Prefecture), Yunnan Province. Methods:From May 2019 to August 2021, a total of 131 samples of Taenia were collected from patients admitted to the Dali Prefecture Institute of Schistosomiasis Control, involving five locations (i.e., five groups), including Dali City (58 samples), Weishan Yi and Hui Autonomous County (Weishan County, 14 samples), Midu County (18 samples), Yangbi Yi Autonomous County (Yangbi County, 24 samples) and Eryuan County (17 samples). Primers were designed based on mitochondrial Cytb gene sequence, and part of the Cytb gene sequence was amplified by PCR, then sequenced and homology comparisons were performed. MEGA 7.0 and DNASP 5.10.01 were used to analyze the measured sequence, and data such as base composition, genetic distance, genetic diversity parameters, genetic differentiation index and gene flow were obtained. Results:The amplified fragments of Cytb gene in 131 samples of Taenia were 235 bp. After homology comparisons, they were all T. asiatica. The average contents of A, T, G and C bases were 23.8%, 42.3%, 24.0% and 9.9%, respectively. Of the 131 samples of T. asiatica, 12 haplotypes were defined. The haplotype diversity and nucleic acid diversity were 0.295 9 and 0.006 0, respectively. The ranges of genetic differentiation index and gene flow among the five groups were-0.053 00 to 0.050 40 and 4.710 31 to 162.087 66, respectively. The genetic distance between the five groups ranged from 0.003 5 to 0.009 0, of which the genetic distance between Midu County and Weishan County was the largest, and the genetic distance between Dali City and Yangbi County was the smallest. Conclusions:The mitochondrial Cytb gene of T. asiatica in Dali Prefecture has rich genetic diversity. There is frequent gene exchange among the five groups, and no significant genetic differentiation has been formed.