Molecular cytogenetic characterization of a duplication of 15q24.2-q26.2 associated with anencephaly and neural tube defect.

OBJECTIVE: We present molecular cytogenetic characterization of a duplication of 15q24.2-q26.2 associated with anencephaly and neural tube defect (NTD).

CASE REPORT: A 35-year-old pregnant woman was found to have a fetus with anencephaly by prenatal ultrasound at 12 weeks of gestation. The pregnancy was subsequently terminated, and a malformed fetus was delivered with anencephaly. Cytogenetic analysis of the cultured placental tissues revealed a karyotype of 46,XX,dup(15) (q24.2q26.2). Parental karyotypes were normal. Array comparative genomic hybridization analysis of the placental tissues revealed a 20.36-Mb duplication of 15q24.2-q26.2 encompassing 100 Online Mendelian Inheritance of in Man (OMIM) genes including LINGO1, MTHFS, KIF7 and CHD2. Metaphase fluorescence in situ hybridization analysis using 15q25.1-specidic probe confirmed a duplication of 15q25.1. Polymorphic DNA marker analysis showed a maternal origin of the duplication.

CONCLUSION: A duplication of chromosome 15q24.2-q26.2 can be associated with NTD.