Prenatal diagnosis and molecular cytogenetic characterization of mosaicism for r(10) and monosomy 10 at amniocentesis in a fetus associated with perinatal growth restriction but no gross structural abnormalities

Abstract

Objective

We present prenatal diagnosis and molecular cytogenetic characterization of mosaicism for r(10) and monosomy 10 at amniocentesis in a fetus with a 10p15.3 microdeletion and a 10q26.3 microdeletion.

Case report

A 37-year-old, gravida 2, para 1, woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 45,XX, −10[11]/46,XX,r(10)[6]. Prenatal ultrasound was normal. She was referred for genetic counseling, and repeat amniocentesis at 21 weeks of gestation revealed a karyotype of 46,XX,r(10)[15]/45,XX,-10[5]. The parental karyotypes were normal. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed a 2.182-Mb 10p15.3 deletion encompassing the genes of ZMYND11 and DIP2C, and a 2.257-Mb 10q26.3 deletion outside the genes of DOCK1 and EBF3. Prenatal ultrasound showed intrauterine growth restriction but no gross structural abnormalities. The parents elected to continue the pregnancy, and a 2425-g baby was delivered at 40 weeks of gestation without craniofacial dysmorphism. The cord blood had a karyotype of 46,XX,r(10)[29]/45,XX,-10[9]/47,XX,r(10),+r(10)[1]/46,XX[1]. When follow-up at age four months, the peripheral blood had a karyotype of 46,XX,r(10) [32]/45,XX,-10[8], her body weight was 5.1 Kg (<3 centile), and body height was 58 cm (<3 centile). She did not have craniofacial dysmorphism. When follow-up at age one year and two months, her body weight was 5.9 Kg (<3 centile), and body height was 68.5 cm (<3 centile). She manifested motor and speech developmental delay but no hypotonia. Brain computed tomography and whole-body ultrasound examination showed no abnormalities.

Conclusion

Mosaicism for r(10) and monosomy 10 at prenatal diagnosis can be associated with perinatal growth restriction but no gross structural abnormalities.