Effect of Reciprocal Translocations on Phenotypic Abnormalities
نویسنده
چکیده
The chromosomal disorders make a significant contribution to human mortality and morbidity. Karyotyping allows the identification of various chromosomes involved in a rearrangement. Chromosomal aberrations occur in approximately 1 in 200 live – born infants and the incidence of reciprocal translocations (rcpts) occur as 1/ 500 live births. Balanced reciprocal translocations can lead to a variety of unbalanced products. In this study, undertaken at the Division of Human Genetics of the Department of Anatomy of St. John’s Medical College, Bangalore, 58 cases of reciprocal translocations were collected from the existing data and the results were compiled. The most important observations noted in this study were: 1. The frequency of rcpts was 4.2% among the chromosomal abnormalities identified in the laboratory. 2. The common chromosomes involved in rcpts were chromosomes 1,2,3,5,7,9 and 22. The comparative site of the breakpoints showed preference at 1q, 2p, 5q, 3q, 7p and 9p. 3. Comparison between the distribution of parental carrier status and the cases, which were de novo, was explained. Parental carrier status was seen in 18 cases (31.03%) and de novo status was seen in the remaining 40 cases
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