The impact of consanguinity on neonatal and infant health.
Open accessAbstract
Marriage between biological relatives is widely popular in many parts of the world, with over 1000 million people living in countries where 20-50+% of unions are contracted between couples related as second cousins or closer. Consanguinity is, however, a controversial topic, in part due to public misunderstanding, complicated by often exaggerated past estimates of the adverse health outcomes. While some consanguineous couples are at high risk of conceiving a child with a genetic disorder, they are a small minority. Thus a multi-population meta-analysis has indicated an excess infant death rate of 1.1% in the progeny of first cousins, and even this figure may be compromised by inadequate control for non-genetic variables. The benefits as well as the disadvantages of consanguineous marriage are assessed and discussed, with specific consideration given to the health of migrant communities in Western countries, among whom first cousin marriage remains preferential.
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Studies that considered data on the frequency of miscarriages reported no or little effect of consanguinity on prenatal losses, while detecting clear-cut effects on postnatal mortality.
“Studies that considered data on the frequency of miscarriages ( i.e. , a gestation age of $ 28 weeks) reported no or little effect of consanguinity on prenatal losses, while detecting clear-cut effects on postnatal mortality (Schull et al. 1970; Bittles and Makov 1988; Bittles and Black 2010b).”
From An Estimate of the Average Number of Recessive Lethal Mutations Carried by Humans (2015) · cites this paper as Bittles and Black 2010b
Section 3 says a large majority of studies found no significant increase in fetal loss, and Section 5 reports elevated postnatal mortality. But Section 3 cautions that fetal-loss studies focused largely on the last trimester and effectively excluded most early-pregnancy losses. The paper therefore does not establish the claimed result specifically for miscarriage frequency. (LLM, conf=0.85)
Experimental — accuracy not yet measuredRegression of the mortality of first-cousin progeny on that of nonconsanguineous progeny in the same population reveals a significant excess mortality in the former.
“Regression of the mortality of first-cousin progeny -for which the F value is 1/16 -on that of nonconsanguineous progeny in the same population reveals a significant excess mortality in the former, which is then translated into the aggregate effect of recessive deleterious mutations.”
From An Estimate of the Average Number of Recessive Lethal Mutations Carried by Humans (2015) · cites this paper as Bittles and Black 2010b
Over the past centuries, consanguineous marriages were a common practice, and the custom remains prevalent in many countries.
“Over the past centuries, consanguineous marriages were a common practice, and the custom remains prevalent in many countries (Bittles and Black 2010a; Hamamy et al. 2011).”
From An Estimate of the Average Number of Recessive Lethal Mutations Carried by Humans (2015) · cites this paper as Bittles and Black 2010a
Our estimate of the average number of recessive lethal mutations per haploid genome is lower than previous estimates of the total number of lethal equivalents per haploid genome (0.56-0.7).
“our estimate of the average number of recessive lethal mutations per haploid genome is lower than the previous estimates of the total number of ' lethal equivalents ' per haploid genome (0.56 -0.7 in Bittles and Neel 1994; Bittles and Black 2010b).”
From An Estimate of the Average Number of Recessive Lethal Mutations Carried by Humans (2015) · cites this paper as Bittles and Black 2010b
The cited paper’s section 3 reports a 0.7% excess stillbirth rate among first-cousin progeny, not 0.7 lethal equivalents per haploid genome. Searches for “lethal equivalents,” “haploid genome,” and the claimed 0.56–0.7 range found no passage giving that estimate in our copy. (LLM, conf=0.76)
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References 14 · Cited by 132
Research works printed but not linked: 15
- Al-Gazali LI. A genetic aetiological survey of severe childhood deafness in the United Arab Emirates. J Trop Pediatr 1998;44:157-60.
- Bittles AH. Consanguinity and its relevance to clinical genetics. Clin Genet 2001;60:89-98.
- Bittles AH. A community genetics perspective on consanguineous marriage. Commun Genet 2008;11:324-30.
- Bittles AH, Speicher M, Antonarakis SE, Motulsky AG. Consanguinity, genetic drift and genetic diseases in populations with reduced numbers of founders. Human genetics-principles and approaches. 4th ed. Heidelberg: Springer; 2009. p. 507-28.
- Bundey S, Alam H. A five-year prospective of the health of children in different ethnic groups, with particular reference to the effect of inbreeding. Eur J Hum Genet 1993;1:206-19.
- Bittles AH, Black ML. Consanguinity, human evolution and complex diseases. Proc Natl Acad Sci USA 2010;107:1779-86.
- Bittles AH, Black ML. Consanguineous marriage and Human evolution. Ann Rev Anthropol 2010;39:193-207.
- Bittles A H, Hamamy H. Endogamy and consanguineous marriage in Arab populations. In: A. Teebi (ed). Genetic disorders among Arab populations, 2nd ed. Heidelberg: Springer 2010; in press.
- Campbell H, Rudan I, Bittles AH, Wright AF. Human population structure, outbreeding and human health. Genome Med 2009;1:91.
- Helgason A, Pálsson S, Guõbjartsson DF, Kristjánsson P, Stefánsson K. An association between the kinship and fertility of human couples. Science 2008;319:813-6.
- McQuillan R, Leutenegger AL, Abdel-Rahman R, Franklin CS, Pericic M, Barac-Lauc L, et al. Runs of homozygosity in European populations. Am J Hum Genet 2008;83: 359-72.
- Obeidat BR, Khader YS, Amarin ZO, Kassawneh M, Al Omari M. Consanguinity and adverse pregnancy outcomes: the north of Jordan experience. Mat Child Hlth J 2010;14:283-9.
- Overall ADJ. The influence of the Wahlund effect on the consanguinity hypothesis: consequences for recessive disease incidence in a socially structured Pakistani population. Hum Hered 2009;67:140-4.
- Shaw A. Negotiating risk: British Pakistanis experiences of genetics. Berghahn: Oxford; 2009.
- Teeuw ME, Henneman L, Bochdanovits Z, Heutink P, Kuik DJ, Cornel MC, et al. Do consanguineous parents of a child affected by an autosomal recessive disease have more DNA identical-by-descent than similarly-related parents with healthy offspring? Design of a case-control study. BMC Med Genet 2010;11:113.
- Authors
- Bittles, A. H., & Black, M. L.
- Affiliations
- Edith Cowan University (AU)
- Murdoch University (AU)
- Corresponding author
- Bittles, A.H.
- Venue
- Early Human Development
- Publisher
- Elsevier BV
- Published
- 2010-11
- Volume
- 86
- Issue
- 11
- Pages
- 737-741
- ISSN
- 0378-3782 (ISSN-L)
- OpenAlex
- W1992347866
- Cited by
- 132
- References
- 14
- Citations by year
- 2026: 2 · 2025: 6 · 2024: 7 · 2023: 16 · 2022: 4 · 2021: 7 · 2020: 8 · 2019: 11 · 2018: 10 · 2017: 6 · 2016: 8 · 2015: 13 · 2014: 17 · 2013: 7 · 2012: 3
- FWCI
- 16.59
- Type
- journal article
- Language
- en
- Open access
- green
- ro.ecu.edu.au
- Locations
- Early Human Development (publishedVersion)
- PubMed (publishedVersion)
- Australasian Journal of Paramedicine (submittedVersion)
- Murdoch University Research Portal (submittedVersion)
- Topics
- Social Sciences › Sociology and Political Science › Marriage and Family Dynamics
- Health Sciences › Health Professions › General Health Professions › Maternal and Neonatal Healthcare
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetic Associations and Epidemiology
- Keywords
- consanguinity, first cousin marriage, infant mortality, newborn health, genetic disorders, immigrant communities, consanguineous couples
- MeSH terms
- Adult, Consanguinity, Female, Humans, Infant, Infant Mortality, Infant Welfare, Infant, Newborn, Infant, Newborn, Diseases, Male, Marriage, Pregnancy, Pregnancy Outcome, Meta-Analysis as Topic, Survival Rate, Reproductive Behavior, Fetal Mortality, Emigrants and Immigrants
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