Multiple congenital anomalies in a fetus with apparently balanced de novo translocation, 46,XY,T(3;8)(Q27-29;Q21)

Apparently balanced de novo translocations detected in prenatal analyses may be associated with phenotypic abnormalities in the fetus. We describe a de novo reciprocal translocation between the long arms of chromosome 3 and 8 in a foetus with multiple congenital anomalies.
A 26-year-old primigravida was referred for genetic counselling because of ultrasonographic findings of cleft lip, pes equinovarus, and single umbilical artery at her 23th week of gestation. Cytogenetic analysis of cordocentesis material revealed 46,XY,t(3;8)(q27-29>;q21) karyotype. Karyotype of the parents were normal. The pregnancy was terminated at 24th week. Post-mortem examination of this male fetus revealed facial dysmorphism characterised by hypertelorism, proptosis, depressed nasal bridge, low-set ears, unilateral cleft lip and palate, absence of left nostril and micrognathia. Claw appearance of the hands, simian crease on the right hand, bilateral pes equinovarus, and hypoplastic right kidney with pelvic localisation were other abnormalities.
Previous prenatal studies show that approximately 6% of de novo reciprocal translocations have a risk of serious congenital anomaly. Normal karyotypes of parents and apparently balanced translocations do not exclude particular hot spots among the breakpoints, causing serious abnormalities in the offspring.