Memorias del Instituto de Investigaciones en Ciencias de la Salud
versão On-line ISSN 1812-9528
TORRES, E et al. Chromosomal abnormalities in both parents of a child with multiple congenital defects. Case report. Mem. Inst. Investig. Cienc. Salud [online]. 2010, vol.8, n.1, pp. 54-58. ISSN 1812-9528.
ABSTRACT This is the case of a couple with a child carrier of congenital defects, deceased at the second day after birth. The karyotype the deceased child was not made and the child was product of the third pregnancy of a mother of 35 years old and a father of 45 years old, both apparently healthy and non-consanguineous. Both parents did not refer any family history of birth defects, pathological background or medicines intake during pregnancy. The couples karyotype was performed on lymphocytes isolated from peripheral blood. All cells from the mother showed and increased heterochromatin on chromosome 9; 2% showed a translocation between chromosomes 2 and 22; and another 2% showed an isochromosome for the long arm of chromosome 1. In the father, 7.5% of the cells showed the presence of a marker chromosome. The mother´s kariotype was 46,XX,9hq+,t(2;22),i(1q) and the father´s was 46,XY/47,XY+mar. While 9qh+ chromosomal is considered normal with no clinical consequences, this condition has been found in couples with infertility and sterility problems. The translocation and the isochromosome found at a very low percentage are considered the most severe chromosomal abnormalities that lead to the production of unbalanced gametes. It would be more feasible to consider the supernumerary marker chromosome as responsible of the birth defects in the child. This background emphasizes the importance of the medical indication of cytogenetic studies in parents of children carriers of multiple malfomrations for the corresponding genetic counseling.
Palavras-chave : Congenital defects; marker chromosome; infertility.