Critical region in 2q31.2q32.3 deletion syndrome: Report of two phenotypically distinct patients, one with an additional deletion in Alagille syndrome region

Background Standard cytogenetic analysis has revealed to date more than 30 reported cases presenting interstitial deletions involving region 2q31-q32, but with poorly defined breakpoints. After the postulation of 2q31.2q32.3 deletion as a clinically recognizable disorder, more patients were reported with a critical region proposed and candidate genes pointed out.