MOLECULAR-CYTOGENETIC INVESTIGATION OF ROBERTSONIAN TRANSLOCATION 13;14 AND DOWN'S SYNDROME IN A THREE-YEAR OLD CHILD

摘要

A rare case of Robertsonian translocation 13;14 of maternal origin combined with regular trisomy of chromosome 21 (46, XX, der(13; 14)(q10; q10)mat, +21) and phenotypical manifestations of Down's syndrome is described. By means of molecular-cytogenetic studies along with ordinary cytogenetic studies it was possible to determine that the extra chromosome 21 in the child is of maternal origin and that nondisjunction of chromosome 21 occurred in the first meiosis in the mother. The possible influence of structural abnormalities in chromosomes 13 and 14 on nondisjunction of chromosome 21 is discussed.