In PLoS Genetics this week, a team of investigators led by researchers at the Washington University School of Medicine report that rs1868402, a SNP in the gene encoding the regulatory sub-unit of protein phosphatase B, is associated with cerebrospinal fluid ptau181 levels, and therefore "rate of decline in Alzheimer's disease." The team's "analyses suggest that genetic variants associated with CSF ptau181 levels may have a greater impact on rate of progression, while genetic variants such as APOE4, that are associated with CSF Aβ42 levels influence risk and onset but not the rate of progression," they write, adding that additional "genome-wide association studies of CSF tau/ptau181 levels should identify novel genetic variants which will likely influence rate of progression of AD."
Researchers at the Vanderbilt University School of Medicine and their international colleagues this week identify new genetic risk variants for type 2 diabetes. Using genotype data from 1,019 T2D cases from a Chinese population, the team found "strong evidence for a novel T2D susceptibility locus at 13q31.1 and ... new independent risk variants near regions 10p13 and 15q22.2." The team replicated their findings in three additional T2D genome-wide association studies of European-American, Korean, and Singaporean-Chinese patients.
Also in PLoS Genetics this week, Premal Shah and Michael Gilchrist at the University of Tennessee show the "effect of correlated tRNA abundances on translation errors and evolution of codon usage bias." Specifically, "using a model of protein translation based on tRNA competition and intra-ribosomal kinetics," Shah and Gilchrist examined the distribution of tRNA abundances across 73 bacterial genomes and found a "consistent positive correlation between tRNA abundances across the genetic code," they write.
And in PLoS One this week, an international research team reports that "the MAGE gene family is frequently mutated in melanoma." In the researchers' mutational analysis of the coding regions of MAGEA1, MAGEA4, MAGEC1, MAGEC2, and MAGEE1 in 27 patients, they found "that melanoma cell lines from 37 percent of patients contained at least one mutated MAGE gene." In their investigation of fresh melanoma samples from 86 patients, the team found that "32 percent of the patients exhibited mutations in one or more MAGE genes."