A case of partial monosomy for the short arm of the chromosome No. 9.

Abstract

On the chromosomal examination for the sex determination of the hermaphroditic patient, a case with a partial monosomy for the short arm of the chromosome no. 9 (pter --* p22) was found. The present article deals with clinical and cytogenetic studies on this case.Case reports.The propositus was a 8-year-old boy. He was born to a 38-year-old father and a 35-year-old mother as the first child. There was no history of abortion, stillbirth, congenital malformations, and consanguinity in this couple. Clinical examinations revealed that her parents were phenotypically normal showing no evidence for mental deficiency. The birth weight of this patient was 2570 g at 40 weeks of gestation.Remarkable clinical signs of the proband were mental retardation, muscular hypotonia, trigonocephaly, low hair line, hypertelorism, epicanthus, upward slanted and small palpebral fissure, hypersupercilia which nearly jointed with each other supranasally, anteverted nostril and flat nasal bridge, long philtrum, high-arched palate, low set ears, malformed auricle, widely spaced nipples, and hypoplastic genitalia; cryptorchism, small penis, hypespadia, and hypoplastic scrotum. No abnormalities on his hand and feet were observed.Cytological findings. Chromosome slides for the study were prepared from leucocyte cultures established from the propositus and his parents. For differential staining, the G-banding procedures were applied to the slides made by the air-drying procedure. Chromosome counts were made with 25-well-delineated metaphases in each. Karyotypes were analysed in 12 cells each by the conventional and G-banding preparations.The propositus had the karyotype with 46 chromosomes involving a 9p-chromosome. The deleted segment of the 9p chromosome corresponded to the band in 9pter--* 9p22. No other chromosomal abnormalities were noted. His father and mother were chromosomally normal with no slight evidence for the aberration.