Consanguinity Associated with Child and Adult Mortality in 24 Asian and African Countries, an Ecological Study

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1 Ianian J ubl Health, Vol. 36, No.1, 2007, Ianian pp J ubl Health, Vol. 36, No.1, 2007, pp Oiginal Aticle Consanguinity Associated with Child and Adult Motality in 24 Asian and Afican Counties, an Ecological Study M Saadat Dept. of Biology, College of Sciences, Shiaz Univesity, Shiaz, Ian (Received 12 Aug 2006; accepted 11 Jan 2007) Abstact Backgound: Although numeous studies have found deleteious effects of inbeeding on childhood and pe-epoductive motality, one question emains inadequately addessed: Dose inbeeding lead to inceased childhood motality ates in counties with high level of consanguinity? Methods: To evaluate the public health impact of inbeeding on offsping motality, the association between mean of inbeeding coefficient (α) and sex specific child and adult motality ates in 24 counties fom Asia and Afica was analyzed. Results: Statistical analysis showed that counties with elatively highe ates of consanguineous maiages have highe motality ates than the counties with lowe consanguinity ates. Also, counties with elatively highe GD pe capita have lowe motality ates. Afte contolling the GD pe capita, significant positive coelations between α and child (Female: =0.4355, df=21, =0.038; Male: =0.3991, df=21, =0.059) motality ates wee obseved. Thee was no significant coelation between α and adult (Female: =0.2977, df=21, =0.168; Male: =0.2207, df=21, =0.312) motality ates, afte contolling fo GD pe capita. Conclusion: It is concluded that consanguinity influences child deaths ate independent of the GD pe capita and that a lage popotion of deaths could be attibuted to inbeeding in seveal counties due to high fequencies of consanguinity. Key wods: Consanguinity, Motality ates, GD, Asia, Afica, Ecological study Intoduction Many studies epoted deleteious effects of inbeeding on motality of offsping. Consanguineous maiages showed significantly highe ates of abotion and still biths plus neonatal, postneonatal, infant, less than 5 y and pe-epoductive motalities in geneal (1-6). Fo counties such as Ian, whee the consanguineous maiages ae common (7), the association between consanguinity and motality, is highly impotant fo public health pogams. Theefoe, the pesent study was done. To evaluate the public health impact of inbeeding on offsping motality the association between mean of inbeeding coefficient (α) and sex specific child and adult motality ates in 24 counties fom Asia and Afica was analyzed. We included the Asian and Afican counties in the pesent study because the pevalence of consanguinity is high in these counties. Mateials and Methods Inbeeding coefficient is the pobability that an individual has eceived both alleles of a pai fom an identical ancestal. In addition this value epesents the popotion of loci at which he is homozygous by descent. At population level, usually the mean of inbeeding coefficient (α) of a population calculated. The F was calculated fo each couple and the α estimated fo each population as descibed peviously (8). Data of mean of inbeeding coefficient (α) was obtained fom the data pesented on the web site In the web site the data wee summaized based on the published aticles in scientific jounals. The mean of inbeeding co- Coesponding autho: Tel: , Fax: , E- mail: saadat@susc.ac.i 35

2 M Saadat: Consanguinity Associated efficients (α) values fo diffeent counties was not elated to a same yea. Child motality is defined as the pobability of dying befoe age 5 y pe 1000 fo specific sex. Adult motality defines as the pobability of dying between 15 and 59 y pe 1000 fo specific sex. The goss domestic poduct (GD) pe capita is the pe capita maket value of the total final output of goods and sevices poduced in a county ove a specific peiod. Data about the motality ates (fo 2001) and GD pe capita (fo 2000) wee obtained fom the data pesented on the Wold Health Oganization web site Inclusion citeia wee location of county (Asia and Afica), and available data about GD pe capita, motality ates, and mean of inbeeding coefficient of the county. Counties including the study wee: Algeia, Bahain, Bangladesh, Egypt, Guinea, Indonesia, Ian, Iaq, Jodan, Kuwait, Lebanon, Malaysia, Nigeia, Oman, akistan, hilippine, Saudi Aabia, Singapoe, Si Lanka, Sudan, Tanzania, Tunisia, Tukey, and UEA. Table 1 shows the counties including the study, α, GD pe capita, and sex specific motality ates of childhood and adulthood of the counties. Coelations between the vaiables wee detemined using paametic eason's coelation coefficient analysis. Moeove the patial coelation coefficient analysis was done. Statistical analysis was pefomed using SSS (vesion 11.5) statistical softwae package. -value less than 0.05 consideed statistically significant. Table 1: Mean of inbeeding coefficients α), GD pe capita, and sex specific motality ates of childhood and adulthood of the study counties Motality ates County α GD a Childhood b Adulthood Female Male Female Male Algeia Bahain Bangladesh Egypt Guinea Indonesia Ian Iaq Jodan Kuwait Lebanon Malaysia Nigeia Oman akistan hilippine Saudi Aabia Singapoe Si Lanka Sudan Tanzania Tunisia Tukey UEA a Child motality is defined as the pobability of dying befoe age 5 pe 1000 fo specific sex. b Adult motality defines as the pobability of dying between 15 and 59 y pe 1000 fo specific sex. 36

3 Ianian J ubl Health, Vol. 36, No.1, 2007, pp Results Table 2 shows the coelation between the study vaiables using the eason's coelation coefficient analysis. Thee ae significant negative coelations between GD pe capita and eithe child o adult motality ates. On the othe hand, thee ae significant positive coelations between the mean of inbeeding coefficient (α and eithe child o adult motality ates. Counties with elatively highe ates of consanguineous maiages had highe motality ates than the counties with lowe consanguinity ates. In addition, counties with elatively highe GD pe capita had lowe motality ates. In ode to show the net coelation between consanguinity and motality ates and ule out the confounding effect of GD pe capita on the motality ates, patial coelation analysis was caied out. Afte contolling the GD pe capita, significant positive coelations between α and sex-specific child (Female: = , df= 21, = 0.038; Male: =0.3991, df= 21, = 0.059) motality ates wee obseved. Thee was no significant coelation between α and adult (Female: = , df= 21, = 0.168; Male: = , df= 21, = 0.312) motality ates, afte contolling fo GD pe capita. Table 2: eason's coelation coefficients between the study vaiables GD α GD Adult female motality ate Adult male motality ate Child female motality ate Adult female motality ate Adult male motality ate Child female motality ate Child male motality ate Note: df= Discussion The key finding of the pesent study is a significant positive coelation between α and child motality ate, afte contolling the GD pe capita, in an ecological study based on data of 24 Asian and Afican counties. The obseved association is in the same diections as that epoted by investigatos fom diffeent populations (1-5, 9-14). Futhemoe the pesent esults confimed ou pevious ecological study which investigated the association between inbeeding and its elevance to ealy and pe-epoductive motality in Ian (6). Geneally, inbeeding is associated with loss of biological fitness (8, 10, 11). In populations whee inbed unions ae common, inceased levels of mobidity and motality caused by the action of detimental ecessive genes can be pedicted. Empiical studies on the pogeny of fist cousins indicate mobidity and motality levels to be highe than in the offsping of unelated couples (12). The contibution of ecessive genes as pedisposing factos in common diseases of adulthood is of geat inteest and significance. Highe levels of inbeeding wee epoted in patients with a ange of majo adult disodes, including some 37

4 M Saadat: Consanguinity Associated common cances and cadiovascula disease (10, 12-14). Impoving socioeconomic conditions, the incidence of envionmental disease is declining in most developing counties such as Aabian States of esian Gulf, whee the socioeconomic cicumstances have become favoable and have tanslated into advanced diagnostic and health cae facilities. Thus genetic disodes now account fo an inceasing popotion of mobidity and death. Theefoe it is concluded that consanguinity influences child deaths ate independent of the GD pe capita and that a lage popotion of deaths could be attibuted to inbeeding in seveal counties due to high fequencies of consanguinity. Finally it should be mentioned that the pesent study has some limitations. Fist of all, the pesent study is an ecological study, theefoe has limitation of ecological studies. Second, GD is not the taget confounding vaiable pe se. So thee would be a cetain degee of esidual confounding still pesent in the calculated patial coelation coefficients. Thid, as mentioned in Mateials and Methods section the mean of inbeeding coefficients (α) fo the study counties was not elated to a same yea. Seveal studies descibed that pevalence of consanguinity maiages ae depended to socio-demogaphic and socio-cultual factos (8, 15, 16). Vey ecently I showed that thee was vey high coelation between pevalence of consanguinity within ethnical populations and pevalence of consanguinity epoted in thei folktales (17). Theefoe, it is suggested that the histoical backgound is vey impotant in attitude and pactice about maiages between elatives (17). Taken togethe, although published values fo the study counties epoted in diffeent yeas, it can not influence so much on the esults pesented hee. Acknowledgement This study was suppoted financially by Shiaz Univesity. Refeences 1. Gant JC, Bittles AH (1997). The compaative ole of consanguinity in infant and childhood motality in akistan. Ann Hum Genet, 61(2): Jode LB (2001). Consanguinity and peepoductive motality in the Utah Momon population. Hum Heed, 52(2): Stoltenbeg C, Magnus, Lie RT, Daltveit AK, Igens LM (1998). Influence of consanguinity and matenal education on isk of stillbith and infant death in Noway, Am J Epidemiol, 148(5): Stoltenbeg C, Magnus, Skondal A, Lie RT (1999). Consanguinity and ecuence isk of stillbith and infant death. Am J ublic Health, 89(4): Mokhta MM, Abdel-Fattah MM (2001). Consanguinity and advanced matenal age as isk factos fo epoductive losses in Alexandia, Egypt. Eu J Epidemiol, 17(6): Saadat M, Mohabatka H (2003). Inbeeding and its elevance to ealy and pe-epoductive motality ates in Ian, an ecological study. Ianian J ublic health, 32(1): Saadat M, Ansai-Lai M, Fahud DD (2004). Consanguineous maiage in Ian. Ann Hum Biol, 31(2): lum M (1954). Computation of inbeeding and elationship coefficients. J Heedity, 45(1): Bittles A (2001). Consanguinity and its elevance to clinical genetics. Clin Genet, 60(2): Tunçbilek E, Koç I (1994). Consanguineous maiage in Tukey and its impact on fetility and motality. Ann Hum Genet 1994 (4); 58: Khlat M, Khouy M (1991). Inbeeding and disease: demogaphic, genetic, and epide- 38

5 Ianian J ubl Health, Vol. 36, No.1, 2007, pp miologic pespectives. Epidemiol Reviews, 13(1): Badanddoza A, Akhtauzzaman M (1994). Inbeeding and congenital heat diseases in a noth Indian population. Clin Genet, 45(6): Al-Abdulkaeem AA, Ballal SG (1998). Consanguinity maiages in an uban aea of Saudi Aabia: ates and advese health effects on the offsping. J Community Health, 23(1): Shami SA, Qaisa R, Bittles AH (1991). Consanguinity and adult mobidity in akistan. Lancet, 338(8772): Bene A, Abdulazzaq YM, al-gazali LI, Micallef R, al-khayat AI, Gabe T (1996). Consanguinity and associated sociodemogaphic factos in the United Aab Emiates. Hum Heed, 46(5): Hussain R (1999). Community peceptions of easons fo pefeence fo consanguineous maiages in akistan. J Biosoc Sci, 31(4): Saadat M (2007). Consanguinity maiages in Ianian folktales. Community Genet, 10(1):