In a paper published online in advance in Nature this week, researchers at Stanford University report on 510 genomic deletions, "which fall almost exclusively in non-coding regions and are enriched near genes involved in steroid hormone signaling and neural function" that produce human-specific phenotypes. For example, the team shows that a deletion in the human androgen receptor gene is "correlated with anatomical loss of androgen-dependent sensory vibrissae and penile spines in the human lineage." Another human-specific loss is associated with the "expansion of specific brain regions in humans," the team reports. Our sister publication GenomeWeb Daily News has more on this study here.
Investigators at Columbia University and elsewhere show that inactivating mutations in CREBBP and sometimes in EP300, "two highly related histone and non-histone acetyltransferases that act as transcriptional co-activators in multiple signaling pathways," are common in B-cell non-Hodgkin's lymphomas. In its investigations, the Columbia-led team found that "about 39 percent of diffuse large B-cell lymphoma and 41 percent of follicular lymphoma cases display genomic deletions and/or somatic mutations that remove or inactivate the HAT [histone acetyltransferase] coding domain of these two genes." The team says that mutations in CREBBP and EP300 are representative of a pathogenetic mechanism shared by B-cell non-Hodgkin's lymphomas, and therefore show therapeutic potential for drugs that target acetylation and deacetylation mechanisms.
Researchers at the St. Jude Children's Research Hospital, along with their colleagues at the National Cancer Institute, also report on mutations in CREBBP, though they associated them with relapsed acute lymphoblastic leukemias. In its re-sequencing studies, the team identified 52 somatic non-synonymous mutations in 32 genes, which in addition to CREBBP include the transcriptional co-activator NCOR1 and the transcription factors ERG, SPI1, TCF4, and TCF7L2, among other genes previously associated with ALL. Furthermore, the team found that "several mutations acquired at relapse were detected in subclones at diagnosis, suggesting that the mutations may confer resistance to therapy," as it writes in Nature this week.
In an advance online publication of Nature Genetics, a team led by investigators at DeCode Genetics shows that "a rare variant in MYH6 is associated with high risk of sick sinus syndrome." Using SNP genotyping and whole-genome sequencing, the team found that a missense mutation in MYH6 is significantly associated with sick sinus syndrome. The researchers also report "that the lifetime risk of being diagnosed with sick sinus syndrome is around 6 percent" for those who do not carry this mutation, but 50 percent for those who do.