Different Skeletal Phenotypes in a Mother and Two Daughters with Short Stature Homeobox-Containing Haploinsufficiency

Haploinsufficiency of the short stature homeobox-containing (SHOX) gene causes Turnerskeletal features such as short metacarpals, cubitus valgus, and Madelung deformity. Wereport the clinical findings of a Japanese family consisting of two daughters with SHOXhaploinsufficiency (46, X, del(X) (p.22.3)) and their mother with 45,X [9]/ 46, X, del(X)(p22.3) [11] karyotype. Physical and auxological examinations revealed a mesomelicappearance, cubitus valgus, a short neck and short stature in the daughters, but on theother hand, only a short neck and short stature in the mother. Radiological studiesindicated markedly curved radii in the daughters, but only mild curvature of the radii inthe mother. Regular menstruation had taken place since the age of 12 yr in the elderdaughter, but the mother had irregular menstruation and she had received fertilitytreatment for pregnancy. The different skeletal phenotypes of the mother and her daughterswith SHOX haploinsufficiency might be due to the mild gonadal estrogen deficiency found inthe mother, which was caused by mosaic Turner syndrome, and the phenotypic variability ofSHOX haploinsufficiency.