SHOX mutations detected by FISH and direct sequencing in patients with short stature

Height is the result of interactions of several factors including those of genetic origin. About 3% of people have short stature and in most of them the cause is unknown.1 Recently, the SHOX gene (short stature homeobox containing gene), mapped on the pseudoautosomal region (PAR1) of the X and Y chromosomes, has been specifically associated with the short stature of patients with Turner syndrome or with Leri-Weill dyschondrosteosis (LWD).2–7 Few data have been reported on the relationship between SHOX mutations and idiopathic short stature. Rao et al 2 reported one change among 91 patients with idiopathic short stature, and Binder et al 8 found a mutation in one out of 68 patients. The largest study was recently published by Rappold et al ,9 who found a frequency of 2.4% of SHOX mutations using fluorescence in situ hybridisation (FISH) on 150 patients and single strand conformational polymorphism analysis (SSCP) on 750 patients. We report a study carried out on 56 patients with short stature of unknown origin detecting SHOX mutations in seven (12.5%) by using FISH and direct sequencing analyses. ### Patients Fifty-six patients, 33 females and 23 males, with a mean age of 12.2 years (range 5-18 years) entered this study. All patients were unrelated, coming from different regions of central and southern Italy. In order to exclude patients with dyschondrosteosis or other diseases associated with short stature, we used the following criteria: (1) height at or below the 3rd centile; (2) absence of obvious skeletal abnormalities on physical examination; (3) absence of other diseases on physical examination and routine analyses; (4) normal bone age; (5) normal hGH values using a polyclonal in house RIA (lower detection limit 0.1 ng/μl, mean intra-assay coefficient of variation 6.9%, and mean interassay coefficient 9.5%); and (6) normal karyotype in 16 metaphases …