Report of a case with partial trisomy 9 mosaicism

Trisomy 9 syndrome and other related abnormalities such as full or mosaic trisomy 9 are very rare human chromosomal disorders. The disorders cause early pregnancy loss or death within 20 days after the birth which is accompanied by complex birth defects. The case reported here is a 26-year-old female, identified with partial trisomy of chromosome 9 by Array comparative genomic hybridization -aCGH, but has a longer life than reported in the medical literature and can give birth. The patient did not have abnormal mental or motor problems; no morphological ultrasound abnormalities; curved thumb and scattered warts on the left hand; gave birth to a healthy son after three consecutive stillbirths. The report has shown diverse clinical manifestations of trisomy 9 mosaic abnormalities in humans, contributing to a rare data source of trisomy 9 mosaic cases. Since then, improve knowledge of genetic counseling for rare cases of trisomy 9 mosaicism, especially in genetic counseling of prenatal diagnosis.