Let’s face it: asexual reproduction is not exactly “fun”. In flowering plants, where some species commonly transition from cross-fertilization to self-fertilization, the effect can come with a loss in genetic variety and ability to eliminate harmful mutations.
At least that’s what a team of researchers, including Khaled Hazzouri from New York University Abu Dhabi, has concluded. The team sequenced the genome of Capsella rubella, a self-fertilizing plant that separated from its cross-fertilizing ancestor Capsella grandiflora less than 200,000 years ago.
Comparing RNA expression and polymorphism patterns between the two Capsella species, they found that C. rubella (the asexual one) had a decreased ability to eliminate harmful mutations compared to its cross-fertilizing ancestor. They also made intriguing comparisons between C. rubella and two species of Arabidopsis. Read more about it here.
Another thing that is really not fun at all is ankylosing spondylitis (AS): a painful inflammatory disease that causes bones in the spine and pelvis to grow abnormally, fusing joints and stiffening movements. This inheritable condition was previously linked to the allele HLA-B *27. However, new research, with contributions from King Abdulaziz University, Jeddah, has identified 13 gene loci also associated with the risk of inheriting AS disease.
The researchers did this by combing known immune-related sections of the genomes of 25,764 participants of European, East Asian and Latin American ancestry. Their findings turned up important clues to understanding how HLA-B *27 is involved in the disease. The results may also help provide an efficient way to screen people with back pain for AS risk. More details here.
Beyond the hood
New research from Carnegie Mellon University seems to have found a good, selfish reason to engage in the relatively selfless activity of volunteering. According to a study published in the journal Psychology and Aging, older adults who volunteer for at least 200 hours a year decrease their risk of hypertension by 40 percent.
The researchers studied 1,164 adults between the ages of 51 and 91 from across the U.S. They interviewed the participants once in 2006 and another time in 2010. All had normal blood pressure levels during the 2006 interview. During both interviews, they measured their level of volunteerism, along with various social and psychological factors.
As it turned out, those who reported at least 200 hours of volunteer work during the initial interview were 40 percent less likely to develop hypertension when compared to those who did not volunteer in the 2010 interview. The researchers also found that the amount of time spent volunteering was what mattered, and not the type of volunteer activity.
However, while it seems to pay to be good, the researchers suggest that the real beneficial effect likely comes from the social connections volunteers make through these activities — evidence consistently suggests that having good social connections promotes healthy aging.