In Nature this week, an international team of researchers present data showing that more than 100 common genetic variants determine the age at which a woman experiences her first menstrual cycle. The age of menarche is heritable and associated with risks for disorders ranging from obesity to breast cancer. To better understand the genetic basis for this, the scientists searched for genes associated with the age of onset of menarche in up to 182,416 women of European descent. They found 123 independent genes at 106 genomic loci associated with age at menarche. Many of these loci show associations with other features of puberty, and numerous variants are found in genes that have been implicated in body mass index and various diseases.
Also in Nature, a team of Chinese investigators and their colleagues report on the identification of genetic signatures of gut microbes associated with liver cirrhosis in individuals of Han Chinese origin — findings that could help in the development of liver disease diagnostics. The researchers compared microbe genomes in 98 patients with liver cirrhosis and 83 healthy controls of Chinese ethnicity, uncovering major changes of gut microbe abundance in patients with liver cirrhosis, primarily as a result of infiltration by species usually found in the mouth. They also discovered unique liver-cirrhosis-specific genes in the microbiota that may serve as markers for disease. GenomeWeb Daily News has more on this study here.
Finally, researchers working in collaboration with The Cancer Genome Atlas Research Network report four new subtypes of gastric cancer in Nature this week. Using six different platforms, the scientists developed a molecular classification of gastric cancer and identified pathways and drivers of the distinct classes. This was then used to describe a new classification scheme that defines four major subtypes of gastric cancer that the researchers says will help with patient stratification and trials of targeted therapies. GWDN also covers this here.