الفهرس 
Introduction and Aim of the workOnly 14 pages are availabe for public view
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Abstract
Fetal sexual differentiation relies on translation of chromosomal sex established at fertilization into gonadal sex and somatic sex as development proceeds. In cases where chromosomal, gonadal, and somatic sex are incongruent in human infants and children, rapid establishment of the diagnosis and implementation of medical and surgical management is of paramount importance, since gender identity is so important to psychological well-being throughout life. In mammals, the requirement for the Y chromosome to achieve testicular differentiation suggested the existence of a Y chromosomal gene responsible for inducing the state of maleness, termed the testis-determining factor (TDF). Subsequently, the search for the TDF was narrowed to the short arm of the Y by cytogenetic analysis of abnormal Y chromosomes. Loss of the Y long arm or formation of an iso-chromosome consisting of duplicated short arms without any long arm material was compatible with male development, whereas in contrast, iso-chromosomes consisting exclusively of long arm material showed female phenotype. Currently, most methods for genotypic sex determination use the detection of Y chromosome in males. The cytogenetic analysis is a conventional method not only to identify sex, but also to detect other chromosomal aberrations. We aim to evaluate of PCR-based method of sex determination as a rapid and simple test for gender assignment. We collect 20 blood samples from cases with suspected to have sex chromosomal aberrations as cases with ambiguous genitalia, pubertal disorders or infertility (eg Turner and Klinefelter syndromes ). And also 20 blood samples from phenotypically normal infants (males and females) as a control group. We used PCR technique: amplification of specific X and Y regions and the results compared to that obtained using routine cytogenetic G and or C banding. The results was as follow : the results of PCR were the same as the results of cytogenetic analysis except in one case of ambiguous genitalia and one case of primary amenorrhea which may result from 1) translocation of the testis-determining factor from the Y to the X chromosome, 2) mutation in an autosomal or X chromosome gene which permits testicular determination in the absence of TDF, and 3) undetected mosaicism with a Y-bearing cell line. And this was proved scientifically. Our study shows that this PCR-based method of sex determination is simple and rapid. The process is complete within 3 hours after obtaining the DNA, compared to 1-2 weeks with the chromosome analysis.