Bhinder Munir Ahmad, Sadia Haleema, Mahmood Nasir, Qasim Muhammad, Hussain Zawar, Rashid Muhammad Mudassar, Zahoor Muhammad Yasir, Bhatti Rashid, Shehzad Wasim, Waryah Ali Muhammad, Jahan Shah
Department of Human Genetics & Molecular Biology, University of Health Sciences, Lahore, 54600, Pakistan.
Balochistan University of Information Technology, Engineering and Management Sciences, Takatu Campus, Quetta, Pakistan.
Ann Hum Genet. 2019 Jul;83(4):214-219. doi: 10.1111/ahg.12308. Epub 2019 Mar 19.
Consanguinity has highly complex and multifaceted aspects with sociocultural as well as biological debates on its pros and cons. The biological upshot of consanguinity includes the increased homozygosity, which results in manifold increased risk of genetic disorders at family and population levels. On the other hand, in addition to social, cultural, political, and economic benefits, consanguineous marriages have biological advantages at the population level. The consequence of consanguineous marriages is an upsurge in the number of homozygous diseased individuals with fewer chances of mating and reduced chances of survival, therefore evolutionarily confining the transmission of disease alleles to future generations and encouraging its elimination from a population. Protective effects of consanguinity have also been observed in a few diseases in different populations. Although attractive for many reasons, nonconsanguineous marriages will cause risk alleles to spread throughout the population, making most individuals carriers, and ultimately will resume the production of recessive diseases in subsequent generations. Although consanguinity, from an evolutionary point of view, is beneficial at the population level, it increases the risk of diseases in the very next generation. Presently, there is no treatment for most of the genetic disorders; we cannot opt for consanguinity for long-term benefits. Nonconsanguineous marriages are a better strategy by which we may delay disease manifestation for some generations until science offers a viable solution.
近亲结婚有着高度复杂和多方面的情况,在社会文化以及生物学层面都存在关于其利弊的争论。近亲结婚在生物学上的结果包括纯合性增加,这导致在家庭和群体层面遗传疾病的风险大幅上升。另一方面,除了社会、文化、政治和经济方面的益处外,近亲婚姻在群体层面也有生物学优势。近亲婚姻的结果是纯合患病个体数量激增,其交配机会减少且生存机会降低,因此从进化角度限制了致病等位基因向后代的传递,并促使其从群体中被淘汰。在不同人群的一些疾病中也观察到了近亲结婚的保护作用。尽管出于多种原因近亲结婚颇具吸引力,但非近亲婚姻会导致风险等位基因在整个人口中传播,使大多数个体成为携带者,并最终在后代中重新引发隐性疾病。虽然从进化角度看,近亲结婚在群体层面是有益的,但它会增加下一代患疾病的风险。目前,大多数遗传疾病尚无治疗方法;我们不能为了长期利益而选择近亲结婚。非近亲婚姻是一种更好的策略,通过这种策略我们可以将疾病表现推迟几代,直到科学提供可行的解决方案。