Lessons learned from a child with a chromosomal abnormality but no major congenital anomalies.

Abstract

A 9-year-old female was referred to Genetics with the possible dual diagnoses of 3p deletion and 9p duplication syndromes based on a chromosomal microarray (CMA) report of an unbalanced chromosomal translocation resulting in 3p deletion and 9p duplication. She was the first child born to non-consanguineous German parents with an unremarkable family history. Her mother had well-controlled type 1 diabetes throughout pregnancy. Our patient was delivered at 38 weeks via caesarean section with a birth weight of 3.28 kg. The perinatal course was otherwise unremarkable. By 7 years of life, she had a history of poor growth due to feeding difficulties. The CMA was requested by her paediatrician as part of initial blood tests to investigate her poor growth. All other tests were normal. She underwent adenoidectomy after which her growth parameters improved. Her CMA showed a 4 Mb terminal loss of 3p26.3–p26.1 which included the four OMIM morbid genes (CHL1, CNTN6, CNTN4, and CRBN) implicated in the characteristic features of 3p deletion. In addition, there was a 4.4 Mb 9p24.1–p24.3 duplication, previously reported in individuals with autism and cognitive delays.