Scientists at the University of California at San Francisco found that two X chromosomes present in the cells of female mammals, contribute to a high life expectancy. About it reported in a press release published on the website MedicalXpress.
Researchers derive genetically modified mice with XX chromosomes, XY chromosomes, while in both groups were the rodents with the ovaries (female gonads) and the testes (male gonads). This was achieved by introducing into the cells of mice with double set of female chromosomes, the sry gene, is usually located on the Y chromosome and involved in the formation of male genitalia. In the laboratory, the animals got up, which is not a sex chromosome (autosomal).
The condition of the mice was observed for several years until they all died or reached the age of 30 months. Although all experimental animals were under the same conditions, the rodents with XX chromosomes lived on average longer than those who had a Y chromosome. In addition, the combination of female gonads and the double row of female sex chromosomes are extended longer life.
According to scientists, the hormones released by the glands of females, promotes longevity, affecting certain biochemical pathway over the life of the mice. So, the mice with female chromosomes and ovaries had the advantage of being as young as 21 months. Rodents with XX chromosomes and male gonads avoided premature death, but at that age, so often died as full-fledged men.
