Prevalence of chromosome 9 abnormalities among pediatric specimens

Abstract

To perform cytogenetic analysis for children, especially newborns suspected for chromosome abnormalities. Peripheral blood or born marrow specimens were respectively cultured in proper media. Karyograms were analyzed following G-banding. Of 154 blood specimens, numerical chromosomal abnormalities were identified in 20 patients, which included 19 with trisomy 21. Structural aberrations were identified in 13 patients, among which chromosome 9 aberrations were seen in 6 cases. These included 3 inversions, 1 deletion, 1 insertion and 1 duplication. All aberrations were located in pericentromere region of chromosome 9 with clinical manifestations including congenital heart disease, peculiar facial appearance, paralysis, dysplasia and/or movement disorder. Chromosome polymorphisms were found in 20 patients, most of which had absence of satellites or variation of heterochromatin on chromosome 9. Of 10 bone marrow specimens from children suspected for acute leukemia, chromosome abnormalities were identified in 5 patients. Cytogenetic analysis is useful for children featuring multiple congenital abnormalities. Chromosome 9 abnormalities and their clinical relevance should attract more attention.