Spotlight into some Abnormalities of Human Chromosome in Saudi Arabia

Middle Eastern cultures are tribal and heavily consanguineous. Marriage between cousins has been part of the culture for millennia leading to "founder" effect and a large number of genetic diseases. Chromosomal abnormalities are the results of alterations in the number or structure of chromosomes causing significant human morbidity and mortality. They are responsible for a large proportion of miscarriages, developmental delay, and disorders of sexual development, congenital malformations and mental retardation. The aim of this study is to screen some of these frequent observed common chromosomal disorders and try to identify the significant reason behind the increase or present of these diseases in our community. Data collection and survey study into different local hospital in Riyadh and cytogenetic lab with a variety of clinical disorders; Down syndrome (DS), Turner’s syndrome (TS) and Klinefelter syndrome; amenorrhea; ambiguous sex and multiple congenital malformations. The most common autosomal abnormalities were DS. Numerical abnormalities were accounted for 353 (41.0%) and structural abnormalities 18 (2.0%), respectively. Various other chromosomal anomalies were also reported. We have reviewed the incidence and distribution of chromosomal abnormalities and found higher rate of chromosomal abnormalities 43.1% in the referred cases. Our data suggest that chromosomal analysis is important tool in the evaluation of genetic disorders but lack of genetic counseling did not help to understand the high frequency of such rare genetic disorder in our community.