Published online Dec 15, 2019. doi: 10.4251/wjgo.v11.i12.1101
Peer-review started: April 18, 2019
First decision: July 31, 2019
Revised: August 18, 2019
Accepted: October 14, 2019
Article in press: October 14, 2019
Published online: December 15, 2019
Processing time: 237 Days and 9.3 Hours
Adenomatous polyposis (AP) is classified according to cumulative adenoma number in classical AP (CAP) and attenuated AP (AAP). Genetic susceptibility is the major risk factor in CAP due to mutations in the known high predisposition genes APC and MUTYH. However, the contribution of genetic susceptibility to AAP is lower and less understood. New predisposition genes have been recently proposed, and some of them have been validated, but their scarcity hinders accurate risk estimations and prevalence calculations. AAP is a heterogeneous condition in terms of severity, clinical features and heritability. Therefore, clinicians do not have strong discriminating criteria for the recommendation of the genetic study of known predisposition genes, and the detection rate is low. Elucidation and knowledge of new AAP high predisposition genes are of great importance to offer accurate genetic counseling to the patient and family members. This review aims to update the genetic knowledge of AAP, and to expound the difficulties involved in the genetic analysis of a highly heterogeneous condition such as AAP.
Core tip: Attenuated adenomatous polyposis (AAP) is a highly genetically and clinically heterogeneous condition in terms of severity, clinical features, heritability, and genetics. The major high predisposition genes APC and MUTYH explain a small fraction of AAP (10%-20%). Several predisposition genes have been recently proposed, and some of them have been validated, but studies addressing their global contribution to AAP genetic predisposition is scarce. Clinicians do not have strong discriminating criteria for the recommendation of genetic testing, and the detection rate is low. Therefore, multigene panel testing and a redefinition of strong clinical criteria could improve the outcome of AAP genetic testing.