Polymorphisms of genes coding for ghrelin and its receptor in relation to colorectal cancer risk: a two-step gene-wide case-control study

Background: Ghrelin, an endogenous ligand for the growth hormone
secretagogue receptor (GHSR), has two major functions: the
stimulation of the growth hormone production and the stimulation of
food intake. Accumulating evidence also indicates a role of ghrelin
in cancer development. Methods: We conducted a case-control study
to examine the association of common genetic variants in the genes
coding for ghrelin (GHRL) and its receptor (GHSR) with colorectal
cancer risk. Pairwise tagging was used to select the 11
polymorphisms included in the study. The selected polymorphisms
were genotyped in 680 cases and 593 controls from the Czech
Republic. Results: We found two SNPs associated with lower risk of
colorectal cancer, namely SNPs rs27647 and rs35683. We replicated
the two hits, in additional 569 cases and 726 controls from
Germany. Conclusion: A joint analysis of the two populations
indicated that the T allele of rs27647 SNP exerted a protective
borderline effect (P-trend = 0.004).