Detoxification enzyme polymorphisms are not involved in duodenal adenomatosis in familial adenomatous polyposis.
BACKGROUND
Patients with familial adenomatous polyposis (FAP) are at high risk of developing duodenal adenomas and carcinomas. Besides germline mutations in the adenomatous polyposis coli (APC) gene, additional factors may influence the age of onset and number of duodenal adenomas. This study compared the genotype distributions of duodenal detoxification enzyme isoforms in patients with FAP and controls.


METHODS
The study included 85 patients with FAP and 218 healthy age- and sex-matched controls. Genotyping of all participants using polymerase chain reaction was performed to detect polymorphisms in isoforms of uridine 5'-diphosphate glucuronosyltransferases (UGTs) and glutathione S-transferases (GSTs): UGT1A1, UGT1A3, UGT1A4, UGT1A6, UGT1A10, UGT2B4, UGT2B7, UGT2B15, GSTA1, GSTP1, GSTM1 and GSTT1.


RESULTS
The variant genotypes of UGT1A3 were less common in patients with FAP than in controls (odds ratio 0.39 (95 per cent confidence interval 0.22 to 0.67)). There were no associations between FAP and the other polymorphic genes. The polymorphisms investigated had no predictive value for the severity of duodenal adenomatosis in patients with FAP.


CONCLUSIONS
Although the variant genotypes of UGT1A3 were less common in patients with FAP than in those without, this did not modulate the severity of duodenal adenomatosis.
Berkhout
M
M
Department of Gastroenterology, Radboud University, Nijmegen Medical Centre, Nijmegen, The Netherlands.
Roelofs
H M J
HM
te Morsche
R H M
RH
Dekker
E
E
van Krieken
J H J M
JH
Nagengast
F M
FM
Peters
W H M
WH
D011125:Adenomatous Polyposis Coli / Q000201:enzymology*; D000328:Adult; D004379:Duodenal Neoplasms / Q000201:enzymology*; D005260:Female; D017491:Genes, APC; D005838:Genotype; D014453:Glucuronosyltransferase / Q000235:genetics*; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic / Q000235:genetics*
D014453:Glucuronosyltransferase; D005982:Glutathione Transferase