Detection of recurrent 4p16.3 microdeletion with 2p25.3 microduplication by multiplex ligation-dependent probe amplification and array comparative genomic hybridization in a fetus from a family with Wolf–Hirschhorn syndrome

Abstract

Objective: We present prenatal diagnosis, genetic counseling, and molecular cytogenetic features of familial recurrence of Wolf–Hirschhorn syndrome (WHS). Materials and methods: A 31-year-old woman was referred to a hospital at 24 weeks of gestation because of abnormal ultrasound findings in the fetus. Her first child was a boy who had growth retardation, mental defect, and a distinctive facial appearance. Based on the conventional cytogenetic analysis, the combined use of multiplex ligation-dependent probe amplification (MLPA) and array comparative genomic hybridization (aCGH) facilitated the prenatal diagnosis and genetic counseling in the fetus. Results of the standard G-banging karyotype analysis of the fetus, the parents, and the boy were normal. Results: The MLPA analysis revealed the same 4p microdeletion accompanied by 2p microduplication in the fetus and the boy. The aCGH analysis revealed a 3.57-Mb 4p16.3 microdeletion or arr [hg19] 4p16.3 (71,552–3,636,893) x1 in the fetus and a 3.29-Mb 4p16.3 microdeletion or arr [hg19] 4p16.3 (71,148–3,360,737) x1 in the boy. The 3.57-Mb 4p16.3 microdeletion encompassed 39 OMIM genes. The 3.29-Mb 4p16.3 microdeletion encompassed 36 OMIM genes. They both included LETM1 and WHSC1. The 2p25.3 microduplication was smaller than 666 kb and encompassed only one OMIM gene, ACP1. Conclusion: The combined use of MLPA and aCGH is an effective way to diagnose recurrent WHS. Although WHS is typically caused by a de novo deletion, prenatal diagnosis and genetic counseling are necessary in the next pregnancy in families that have suffered such cases.

Keywords

• array comparative genomic hybridization
• genetic counseling
• multiplex ligation-dependent probe amplification
• prenatal diagnosis
• Wolf–Hirschhorn syndrome