THE IMPORTANCE OF KARYOTYPE TEST IN DIAGNOSING GENETIC DISEASES: A CROSS-SECTIONAL STUDY

Background & Aims: The study of karyotype in several cases is the first step in the diagnosis of genetic disorders. The purpose of this study was to investigate the karyotype of a number of individuals with a range of possible genetic disorders. Materials & Methods: This researchis a descriptive cross-sectional study. Sampling was done after obtaining necessary permissions and written consent from the parents of mentally retarded individuals and individuals with infertility and cancer problems. Blood samples were taken from 200 individuals with a history of recurrent abortions and infertility, including 124 women and 76 men, 40 patients with different types of cancers, and 180 mentally retarded subjects, and then they were determined by cytogenetic karyotype. Results: Out of 180 mentally retarded subjects, 12 (6.6%) had a chromosomal abnormality (8 structural chromosomal abnormalities and four men with fragile X syndrome) and 172(92.4%) subjects had normal karyotypes. Also, of 200 subjects with infertility and abortion, 138 (69%) had healthy karyotype and 62 (31%) had one chromosomal defect. Among 40 patients with cancer, only 2 (0.8%) chromosomal changes were observed. Conclusion: Seventy-three chromosomal changes (62 in infertility, 8 in mental retardation, 2 in cancer and 1 in structural disorder of fragility X) were shown in Karyotype of 420 cases. The findings imply the necessity of performing karyotype in infertility and abortion problems. Further research is needed on mental retardation and cancer.