Resumo

TORRES, E, MONJAGATA, N, HERREROS, MB et al. Monosomía Parcial del Brazo Corto del Cromosoma 9. Pediatr. (Asunción), dez. 2009, vol.36, no.3, p.219-222. ISSN 1683-9803.

Worldwide, approximately 100 cases of partial monosomy of the short arm of chromosome 9 have been reported. The condition is a rare structural anomaly of the chromosome that in approximately 85% of cases represents a deletion due to a mutation that is de novo, sporadic, and spontaneous. The mutation occurs very early in embryonic development for reasons that are yet unknown, and generally involves a portion of the chromosome 9p22. This chromosomal condition may be suspected from birth due to phenotypic facial characteristics and the presence of deep palm creases. We describe a 15-year old female patient on whom a cytogenetic study was done due to mental retardation and various malformations. The chromosomal study, done using peripheral blood, showed 46,XX of the 9p22. Early performance of cytogenetic studies in patients with mental retardation and malformations is important in establishing a diagnosis and prognosis for the patient and for performing the appropriate family genetic counseling.

Palavras-chave: Monosomy; chromosome 9; malformation; mental retardation; chromosome disorders.