3M Syndrome: An Easily Recognizable yet Underdiagnosed Cause of Proportionate Short Stature

Objective To characterize, via clinical and molecul criteria, a cohort of patients with 3M syndrome and thereby increase awareness of this syndrome as a recognizable cause of proportionate short stature. Study design We conducted a case series of patients referred to clinical genetics for proportionate short stature. CUL7 , OBSL1 , and CCDC8 genes were clinically phenotyped and sequenced. Results In 6 Saudi families with 3M syndrome, we identified three CUL7 , one OBSL1 , and one CCDC8 novel mutations, which we show result in a remarkably similar clinical phenotype. Despite their typical and easily discernible clinical phenotype, all these patients have been extensively investigated for alternative causes of their short stature and received erroneous diagnoses. Conclusion Increased awareness about this syndrome among pediatricians and endocrinologists is needed to avoid a costly and unnecessary diagnostic odyssey.