Intrauterine growth retardation and multiple malformations ascertained by echography allowed prenatal diagnosis of penta X syndrome at the 35th week of gestation. The proband's phenotype at birth was consistent with the antenatal observations and the clinical phenotype described in previous patients. The main clinical features were somatic hypodevelopment as compared to gestational age, craniofacial anomalies, congenital heart defects, and agenesia of the right kidney and ureter. Analysis of X-linked RFLPs in the parents and the proband allowed the maternal origin of the three extra X chromosomes to be established, suggesting consecutive nondisjunction events: one in meiosis I and the second, involving both X chromosomes, in meiosis II. Neither maternal age nor familial recurrence of chromosomal aneuploidies was a predisposing cause for the sequential nondisjunction in this case.
- Pentasomy X
- X-linked RFLPs
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health
- Obstetrics and Gynaecology