Single nucleotide polymorphisms of the APC gene and colorectal cancer risk: a case-control study in Taiwan.
BACKGROUND
Colorectal cancer (CRC), which has become especially prevalent in developed countries, is currently the third highest cause of cancer mortality in Taiwan. Mutation of the adenomatous polyposis coli (APC) gene, a tumour suppressor, is thought to be an early event in colorectal tumourigenesis. To date, however, no large-scale screening for APC gene variants in Chinese subjects has been performed. The present study was undertaken to identify APC gene variants that are significantly associated with the occurrence of CRC in Taiwanese subjects.


METHODS
In order to compare the genotype distribution of variant sites, the full-length APC genes of 74 healthy individuals and 80 CRC patients were sequenced.


RESULTS
Among the 154 Taiwanese subjects examined in this study, three new mutations, but no previously reported mutations, were found. One deletion at codon 460 leading to a frameshift and two missense mutations resulting in p.V1125A and p.S1126R substitutions were identified. Additionally, three high risk genotypes associated with three single nucleotide polymorphisms and one low risk genotype at codon 1822 were identified.


CONCLUSIONS
The findings of this case-control study are consistent with the proposal that Taiwanese subjects differ from other subjects with respect to phenotypic presentation of APC and CRC risk.
Chen
Shee-Ping
SP
Institute of Medical Sciences, Buddhist Tzu Chi University: 703, Section 3, Chung-Yang Road, 970 Hualien, Taiwan. asdinap@yahoo.com.tw
Tsai
Shih-Tzu
ST
Jao
Shu-Wen
SW
Huang
Yen-Lun
YL
Chao
Yu-Chen
YC
Chen
Yi-Lin
YL
Wu
Chang-Chieh
CC
Lin
Shinn-Zong
SZ
Harn
Horng-Jyh
HJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D004252:DNA Mutational Analysis; D005260:Female; D016368:Frameshift Mutation; D017491:Genes, APC; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D020125:Mutation, Missense; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D013624:Taiwan