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Short stature due to SHOX deficiency represents the most commonly known form of growth failure, with a frequency greater than 1:1,000 in the Caucasian population. As many different mutations can cause SHOX haploinsufficiency, a comprehensive collection of gene variants represents an essential tool to distinguish between functional variants and polymorphisms. We have created a novel and widely extended SHOX database using the "LOVD in a box-solution." This database contains not only a larger amount of mutation data (140 novel mutations were added), but also reports on phenotypic consequences, mode of inheritance, and ethnic origin, as well as on functional consequences of mutations investigated. In addition, the database now includes non-disease-related polymorphisms to enable researchers to evaluate their diagnostic findings. The database (Available at: http://hyg-serv-01.hyg.uni-heidelberg.de/lovd/index.php?select_db=SHOX; Last accessed: 12 April 2007) contains all presently known 199 intragenic mutations (SNPs as well as small deletions and insertions), 126 of which are unique. The remote user is able to search the data and to submit new mutations into the database. Furthermore, it includes general information about the SHOX gene via links to other resources such as MIM, GDB, HGMD, and HAPMAP, as well as websites of Short Stature Associations., (Copyright 2007 Wiley-Liss, Inc.)

Haploinsufficiency of the short stature homeobox gene SHOX has been found in patients with idiopathic short stature (ISS) and Leri-Weill dyschondrosteosis (LWD). In addition to complete gene deletions and nonsense mutations, several missense mutations have been identified in both patient groups, leading to amino acid substitutions in the SHOX protein. The majority of missense mutations were found to accumulate in the region encoding the highly conserved homeodomain of the paired-like type. In this report, we investigated nine different amino acid exchanges in the homeodomain of SHOX patients with ISS and LWD. We were able show that these mutations cause an alteration of the biological function of SHOX by loss of DNA binding, reduced dimerization ability, and/or impaired nuclear translocation. Additionally, one of the mutations (c.458G>T, p.R153L) is defective in transcriptional activation even though it is still able to bind to DNA, dimerize, and translocate to the nucleus. Thus, we demonstrate that single missense mutations in the homeodomain fundamentally impair SHOX key functions, thereby leading to the phenotype observed in patients with LWD and ISS.