Clinical findings and molecular cytogenetic study of de novo pure chromosome 9p deletion: Pre- and postnatal diagnosis

Abstract

Objective: The aim of this report is to describe the phenotype-genotype correlation of chromosome 9p deletion syndrome cases, particularly the prenatal cases. Case report: We present a female fetus at 17+4 weeks of gestation age detected with an 8 × 6 mm2 omphalocele. Karyotype analysis of the fetus cell showed a karyotype of 46,XX,del(9)(p22). Whole genome array comparative genomic hybridization analysis detected a deletion as arr 9p24.2p22.2 (226,7812–1,7466,907 bp) × 1. The prenatal abnormality and cytogenetic findings in our and other similar patients are compared. Moreover, we describe two male cases demonstrating de novo and pure 9p deletion at 9p24.3p22.1 (1–18,743,296 bp) and 9p24.3p23 (271,257–12,048,612 bp). These two children shared development delay, learning difficulties, hypotonia, and trigonocephaly. However, both the boys apparently did not present external genitalia malformation, although the deletion region included the sex reversal region 9p24.3. Conclusion: Phenotypes of 9p deletion cases are broadly in line. The prenatal diagnosis of the omphalocele provides evidence for a correlation with distal 9q deletion.

Keywords

• chromosome 9p deletion syndrome
• de novo
• prenatal
• ultrasound