根據(jù)發(fā)表在《進(jìn)化》（Evolution）上的文章，對(duì)某些傳染類疾病的抵抗力可能通過父母遺傳給后代,。擁有這類基因抵抗力的家族無疑是幸運(yùn)的，他們既不會(huì)患上相關(guān)疾病,，又不會(huì)將這些疾病帶回家中,。文章的作者Paul Schliekelman表示，這一研究受到了他自己經(jīng)歷的啟發(fā),，作者曾在6個(gè)月內(nèi)被女兒傳染急性胃腸炎3次,。
Schliekelman利用數(shù)學(xué)模型計(jì)算出了“親緣選擇”在自然進(jìn)化中可能的作用。他表示：“自然選擇通常被看作是‘適者生存’,，但在我們的研究中稱它為‘合適的家庭生存’可能更準(zhǔn)確,。”
Schliekelman研究取得的成果主要包括：從家庭成員那里被傳染疾病的可能性非常高；如果有一位親屬擁有對(duì)一種疾病的抵抗力基因,，那其他家庭成員感染相同疾病的幾率也會(huì)更?。粚?duì)疾病的抵抗力基因容易在家庭中叢發(fā)性出現(xiàn),；因此抵抗力基因一般能幫助家族中的每個(gè)人防御疾病,，并且這種自然選擇會(huì)大幅度提升。
研究使用的模型對(duì)于了解致命疾病的傳播非常有效,，而且可能改變?nèi)巳褐刑囟ɑ虻拈L期自然選擇,。研究這些疾病的基因行為是邁向了解傳染病抵抗力進(jìn)化歷史的重要一步。 （教育部科技發(fā)展中心）
原文鏈接：http://www.physorg.com/news107705954.html
原始出處:
Volume 61 Issue 6 Page 1277-1288, June 2007
To cite this article: Paul Schliekelman (2007)
KIN SELECTION AND EVOLUTION OF INFECTIOUS DISEASE RESISTANCE
Evolution 61 (6), 1277–1288.
doi:10.1111/j.1558-5646.2007.00122.x
KIN SELECTION AND EVOLUTION OF INFECTIOUS DISEASE RESISTANCE
Paul Schliekelman11Department of Statistics, University of Georgia, Athens, Georgia 30602–1952 E-mail: [email protected] 1Department of Statistics, University of Georgia, Athens, Georgia 30602–1952 E-mail: [email protected]
Discoveries of mutations conferring resistance to infectious diseases have led to increased interest in the evolutionary dynamics of disease resistance. Several recent papers have estimated the historical strength of selection for mutations conferring disease resistance. These studies are based on simple population genetic models that do not take account of factors such as spatial and family structure. Such factors may have a substantial impact on the strength of natural selection through inclusive fitness effects. That is, people have a strong tendency to live with relatives and therefore have a high probability of transmitting infectious diseases to them. Thus, an allele that protects an individual against disease infection also protects that individual's family members. Because some of these family members are likely to also be carrying the allele, selection for that allele is magnified by family structure. In this paper, I use mathematical modeling techniques to explore the impact of such kin selection on the strength of selection for infectious disease resistance alleles. I show that if the resistance allele has the same proportional effect on both within- and between-family transmission, then the impact of kin selection is relatively minor. Selection coefficients are increased by 5–35%, with a greater benefit for weaker alleles. The reason is that an individual with a strong resistance allele does not need much protection from infection by family members and thus does not benefit much from their alleles. The effect of kin selection can be dramatic, however, if the resistance allele has a larger effect on between-family transmission than within-family transmission (which can occur if between-family infection rates are much smaller than within-family rates), increasing selection coefficients by as much as two- to threefold. These results show conditions when it is important to consider family structure in estimates of the strength of selection for infectious disease resistance alleles.
