(HealthDay News) – There is an association between an increase in the degree of germline allele-specific expression (ASE) of the adenomatous polyposis coli (APC) gene and the risk of common forms of colorectal cancer (CRC), according to a study published in the January issue of Gastroenterology.
Maria Cristina Curia, MD, of “G. d’Annunzio” University in Chieti, Italy, and colleagues investigated the role of germline variations in ASE in CRC. To do this, blood samples from 53 CRC cases and 68 controls were analyzed using high-performance liquid chromatography for the degree of variation in ASE in the APC gene. Screening for sequence variants and single-nucleotide polymorphism genotyping was also performed.
Compared with controls, the researchers found patients with CRC to be at a 3.97-fold increased risk of CRC if their ASE deviated more than one standard deviation from the mean, and they were at a 13.46-fold increased risk of CRC if their ASE deviated more than 1.645 standard deviations from the mean. A nonsense mutation in APC (p.Arg216X) was found in a patient without a family history of CRC but who had a high level of ASE.
“CRC risk appeared to increase proportionally with the degree of APC ASE, providing evidence that imbalanced ASE of APC is a novel promising indicator of CRC predisposition. These data support the conclusion that the same genes that predispose to rare, highly penetrant, familial cancer may act in apparently sporadic cancer by mechanisms causing ASE,” the authors write.