Consanguinity among theSaudiArabian population

Thisstudywas conducted on 3212Saudi families toinvestigate theprevalence of consanguineous marriages. The families were interviewed andtheinformation on therelationship betweenthehusbandand wifewas obtained. Theoverall rateofconsanguinityshowsthat57-7%ofthefamilies screened were consanguineous. Themost frequent were firstcousinmarriages (28-4%) followed bydistant relative marriages(15-2%)and secondcousinmarriages (14-6%). Thefamilies were groupedaccording to theprovince oftheirorigin andtheconsanguinityrates were calculated accordingly. Therewere slight differences in theconsanguinity ratesinthefiveprovinces, whichrangedfrom52-1%to67-7%. Ineachprovince first cousinmarriages were themostfrequently encountered pattern,rangingfrom17-90/o to 40-90/o. The inbreeding coefficient (F)was calculated foreachprovince andrangedfrom0-020 to0O030. Withineachprovince, there were several significant differences among thepopulations inthedifferent areas.Thehighest rateofconsangiinity was 80O6%inSamtah andthelowestratewas around34% in AbhaintheSouthWesternprovince. Theseresults placeSaudiArabia among thecountries oftheworldwitha high rateofconsanguinity. Thepossible consequences ofincreased consanguinity are presented anddiscussed. (.JMed Genet1995;32:623-626)