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Updated: Aug 11, 2026

FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
Cytogenetics of genetic counseling patients in Pelotas, Rio Grande do Sul, Brazil
A C Duarte1, E Cunha, J M Roth
1Serviço de Aconselhamento Genético, Departamento de Zoologia e Genética, Instituto de Biologia, Universidade Federal de Pelotas, Pelotas, RS, Brasil.
Abstract:
From 1986 to 2002, we examined the chromosomal composition of 916 patients attended by two genetic counseling services in the city of Pelotas, in the Brazilian State of Rio Grande do Sul, to determine the genetic causes of their disturbances. Patterns of G-banding using trypsin and Giemsa (GTG) and C-banding using barium and Giemsa (CBG) were studied using phytohemagglutinin M-stimulated lymphocytes cultured from peripheral blood. Among the patients, 110 had Down's syndrome, 7 had Edward's syndrome, 4 had Patau's syndrome, 29 had Turner's syndrome, 5 had Klinefelter's syndrome, and 3 had "cri-du-chat" syndrome. Abnormal chromosomes were observed in 29.3% of the patients. Most of these (56.3%) were numerical abnormalities, with the remaining being structural variants.
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