OBSL1 and 3-M syndrome: In 2005, Huber et al. (2019) initially reported that CUL7 variants accounted for 77.5%, OBSL1 variants 16.3%, and CCDC8 variants 6%, of 3M syndrome cases; however, with continued research, changes in CUL7 were found to be responsible for the majority of cases, while OBSL1 mutations were present in more than 16.3% and those in CDCC8 less than 6%.