日本东京农业大学的科学家团队发现，拥有两个生物学上的母亲但没有父亲的老鼠的寿命比普通老鼠长30%，这或许表明，遗传自父亲的基因可能会缩短其后代的寿命。相关研究发表在12月2日出版的《人类生殖学》杂志上。
新研究是东京农业大学河野友宏团队正在进行的另一项研究的“副产品”。2004年，该团队采用一种无需雄性的生殖技术，成功地用两枚未受精的卵子培育出一只名为“辉夜姬”（Kaguya，日本童话故事中的人物，角色相当于“月亮公主”）的单性生殖老鼠，该老鼠没有生物学上的父亲，是世界上首例单性生殖哺乳动物。
单性生殖常见于爬行动物和昆虫。“辉夜姬”的诞生首次说明，通过单性生殖这一“无配子生殖”现象培育哺乳动物是可能的。最后，“辉夜姬”活了793天，而其同系的老鼠仅活了600天到700天。
为了弄清是否“辉夜姬”独特的出生方式有助于其长寿，河野友宏团队接着培育出了另外13只也是由两个卵子得到的“双母亲老鼠”，并将其与正常情况下得到的老鼠进行对照研究。结果显示，“双母亲老鼠”比正常老鼠平均多活186天。但是，“双母亲老鼠”明显比正常的老鼠要小、要轻。
河野友宏认为，这表明来自于父亲精子的某些被印记了的基因可能会抑制寿命，同时增大体型。
研究人员表示，到目前为止，该影响是否适用于人类还不得而知，但是，该研究可让人们从新的角度来理解基因对哺乳动物衰老过程的影响。（生物谷Bioon.com）
生物谷推荐原始出处：
Human Reproduction December 1, 2009, doi:10.1093/humrep/dep400
Longevity in mice without a father
Manabu Kawahara1 and Tomohiro Kono2,3
1 Laboratory of Animal Resource Development, Faculty of Agriculture, Saga University, 1 Honjo-machi, Saga 840-8502, Japan 2 Department of BioScience, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan
BACKGROUND: Females live longer than males in many mammalian species, including humans. It has been observed that women are at an advantage over men with regard to the lifespan; however, the reason for this sex difference in longevity is unclear. Bi-maternal mice (BM), which are produced in a ‘sperm-free’ manner, could provide an opportunity to analyse the longevity of animals lacking paternal genomes.
METHODS AND RESULTS: We studied the longevity of BM, which were generated using two sets of female genomes—one derived from fully grown oocytes from normal adults and the other from non-growing oocytes from newborn pups. These newborn pups were also genetically manipulated in two regions—the imprinting centres of Igf2-H19 and Dlk1-Gtl2—on chromosomes 7 and 12. We determined lifespan of the control (n = 13) and BM (n = 13). Our results revealed that the bi-maternal genotype clearly shifted the entire survival curve to the right, suggesting a delay in the expression of all causes of mortality. BM survived 186 days longer than controls. Furthermore, the body weight was significantly lower in the BM as compared with the controls at 20 months after birth (P < 0.05), and leukocyte composition analysis at 8 weeks revealed that the eosinophil count was significantly increased in the BM as compared with the controls (P < 0.05, n = 6).
CONCLUSIONS: These findings demonstrate that the maternal genome may play a role in ontogenetic longevity. Our results further suggested sex differences in longevity, originating at the genome level, implying that the sperm genome has a detrimental effect on longevity in mammals.
