|Budget Amount *help
¥13,700,000 (Direct Cost: ¥13,700,000)
Fiscal Year 2003: ¥4,200,000 (Direct Cost: ¥4,200,000)
Fiscal Year 2002: ¥4,100,000 (Direct Cost: ¥4,100,000)
Fiscal Year 2001: ¥5,400,000 (Direct Cost: ¥5,400,000)
A total of 200 Japanese nonsyndromic oral clefts probands and their parents were recruited for this study. Each of ten probands had an affected parent. Written and oral informed consent was obtained from all subjects. This study was approved by the Ethics Committee of Tohoku University School of Medicine.
The first, we analyzed the association between nonsyndromic oral clefts (cleft lip, cleft palate, and cleft lip and palate) and candidate genes (MSX1,TGFA, TGFB2,TGFB3,RARA, GAD67 and MTHFR), which were suggested to save significant association in Caucasian. The result indicated that only GAD67 have significant associations in Japanese populations.
The next, in order to assess whether environmental factors such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) play a significant roll for the etiology of nonsyndromic oral clefts, we assessed whether there is any association in the Japanese population of nonsyndromic oral clefts and single nucleotide polymorphisms (SNPs) in AHR, ARNT, and CYP1A1 which are involved in TCDD metabolism using transmission disequilibrium test (TDT) and case-control study. We identified and investigated three SNPs in ARNT. Two amino acid substitutions in AHR and CYP1A1 were also investigated. Our results suggest that ARNT is involved in the development of nonsyndromic oral clefts in the Japanese population.