A Rare Cause of Short Stature: 3M Syndrome in a Patient with Novel Mutation in OBSL1 Gene

Abstract

The Miller-McKusick-Malvaux (3M) syndrome is a rare autosomal disorder that can lead to short stature, dysmorphic features, and skeletal abnormalities with normal intelligence. A 16-month-old female patient had been referred to our clinic due to short stature. Case history revealed a birth weight of 1740 grams on the 39 ^th week of gestation, with a birth length of 42 cm and no prior hereditary conditions of clinical significance in her family. On physical examination, her length was 67 cm [-3.6 standard deviation (SD) score], weight 7.2 kg (-2.9 SD score), and head circumference 42 cm (below 3 ^rd percentile). She also had numerous characteristic physical features such as a triangular face, fleshy nose tip, a long philtrum, prominent mouth and lips, pointed chin, lumbar lordosis, and prominent heels. As her growth retardation had a prenatal onset and the physical examination results were suggestive of a characteristic profile, the diagnosis of 3M syndrome was strongly considered. Genetic assessment of the patient revealed a novel homozygous p.T45Nfs*40 mutation in the OBSL1 gene. It is recommended that physicians pay further attention to this condition in the differential diagnosis of children with severe short stature.