Prenatal diagnosis of a familial 9p12 amplification inherited from a father carrier

Abstract

Objective: We present prenatal diagnosis of a familial 9p12 amplification inherited from a father carrier.

Case report: A 38-year-old, gravida 3, para 2, woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a heteromorphic variant of chromosome 9 with a 9p12 amplification on G-band preparations, but it was negative on C-band preparations. Cytogenetic analysis of the parents revealed that the phenotypically normal father carried the same euchromatic 9p + polymorphism. Array comparative genomic hybridization analysis on the DNA extracted from the father's blood revealed no genomic imbalance. At 37 weeks of gestation, a healthy 2760-g female baby was delivered with no phenotypic abnormality. She was doing well at age one year during follow-up.

Conclusion: Prenatal diagnosis of a 9p + variant can be a euchromatic chromosome variant of a familial 9p12 amplification without phenotypic consequences.

Keywords: 9p12 amplification; Euchromatic chromosome variant; Prenatal diagnosis.