Genetic factors play a crucial role in determining human height. Short stature commonly affects multiple family members and therefore, familial short stature (FSS) represents a significant proportion of growth disorders. Traditionally, FSS was considered a benign polygenic condition representing a subcategory of idiopathic short stature (ISS). However, advancements in genetic research have revealed that FSS can also be monogenic, inherited in an autosomal dominant manner and can result from different mechanisms including primary growth plate disorders, growth hormone deficiency/insensitivity or by the disruption of fundamental intracellular pathways. These discoveries have highlighted a broader phenotypic spectrum for monogenic forms of short stature, which may exhibit mild manifestations indistinguishable from ISS. Given the overlapping features and the difficulty in differentiating polygenic from monogenic FSS without genetic testing, some researchers redefine FSS as a descriptive term that encompasses any familial occurrence of short stature, regardless of the underlying cause. This shift emphasizes the complexity of diagnosing and managing short stature within families, reflecting the diverse genetic landscape that influences human growth.

• Keywords
• autosomal dominant short stature, familial short stature, genetics, growth plate, short stature,
• MeSH
• Phenotype MeSH
• Humans MeSH
• Dwarfism genetics   MeSH
• Growth Disorders * genetics   MeSH
• Body Height * genetics   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

Familial short stature (FSS) describes vertically transmitted growth disorders. Traditionally, polygenic inheritance is presumed, but monogenic inheritance seems to occur more frequently than expected. Clinical predictors of monogenic FSS have not been elucidated. The aim of the study was to identify the monogenic etiology and its clinical predictors in FSS children. Of 747 patients treated with growth hormone (GH) in our center, 95 with FSS met the inclusion criteria (pretreatment height ≤-2 SD in child and his/her shorter parent); secondary short stature and Turner/Prader-Willi syndrome were excluded criteria. Genetic etiology was known in 11/95 children before the study, remaining 84 were examined by next-generation sequencing. The results were evaluated by American College of Medical Genetics and Genomics (ACMG) guidelines. Nonparametric tests evaluated differences between monogenic and non-monogenic FSS, an ROC curve estimated quantitative cutoffs for the predictors. Monogenic FSS was confirmed in 36/95 (38%) children. Of these, 29 (81%) carried a causative genetic variant affecting the growth plate, 4 (11%) a variant affecting GH-insulin-like growth factor 1 (IGF1) axis and 3 (8%) a variant in miscellaneous genes. Lower shorter parent's height (P = 0.015) and less delayed bone age (BA) before GH treatment (P = 0.026) predicted monogenic FSS. In children with BA delayed less than 0.4 years and with shorter parent's heights ≤-2.4 SD, monogenic FSS was revealed in 13/16 (81%) cases. To conclude, in FSS children treated with GH, a monogenic etiology is frequent, and gene variants affecting the growth plate are the most common. Shorter parent's height and BA are clinical predictors of monogenic FSS.

• Keywords
• GH treatment, familial short stature, growth plate disorders, next-generation sequencing, predictors of monogenic short stature,
• Publication type
• Journal Article MeSH