Unique deletion in exon 5 of SHOX gene in a patient with idiopathic short stature.

BACKGROUND/AIM: It is known that haploinsufficiency for the SHOX gene (short-stature homeobox gene on the X chromosome) is responsible for short stature in Turner syndrome and Leri-Weill dyschondrogenesis, and it has been reported that it is responsible for upwards of 1 in 50 cases of idiopathic short stature. SHOX haploinsufficiency is also associated with various radiographic abnormalities, such as coarse trabecular pattern, short metacarpals/metatarsals with metaphyseal flaring, altered osseous alignment at the wrist, radial/tibial bowing, triangularization of the radial head, abnormal tuberosity of the humerus, and an abnormal femoral neck. Shortening and bowing of the radius and dorsal dislocation of the distal ulna characterize the Madelung deformity. These characteristic findings led us to do a study assessing the predictive value of certain radiographic features in association with genetic markers of idiopathic short stature.

METHODS

Here we describe a case of a Hispanic male with idiopathic short stature and Madelung deformity with a novel mutation in the SHOX gene.

RESULTS

Additional studies revealed a strong family history of short stature and the same SHOX mutation segregating from the mother.

CONCLUSION

This case resulted in the description of a novel mutation in exon 5 (M202delA) and suggests the importance of screening for SHOX mutations in patients with idiopathic short stature with subtle radiographic abnormalities, including the components of the Madelung deformity in their bone age films.