Identification of casual mutations in Hereditary Multiple Exostoses
(HME) is important because of similar conditions in which multiple exostoses
occur. Therefore mutation analysis can help to confirm the clinical diagnosis
and to improve the management of therapy. HME is an inherited disorder
of bone growth. HME can be referred to by various names such as Heredity
Multiple Exostoses, Hereditary Multiple Osteochondromata, Multiple Carthaginous
Exostoses, etc. People who have HME grow exostoses, or bony bumps, on
their bones which can vary in size, location and number depending on the
individual. HME is inherited in an autosomal dominant manner with an estimated
prevalence of 1/50,000 in western countries. At least three loci (EXT1,
EXT2 and EXT3) thought to be involved in this skeletal disease. Approximately
90% of affected families possess mutations in the coding regions of EXT1
and EXT2 genes and the majority of these mutations cause loss of function.
EXT1 and EXT2 genes encode related members of a putative tumor suppressor
family. In this first report from Iran we identified a frame shift mutation
(1100-1101 insA) in exon 3 of EXT1 gene in a family being suspicious of
HME. This mutation leads to a premature stop codon and previously not
described. Additionally, we have found an unreported silent mutation in
the exon six of EXT1 gene with uncertain significance.
Ali Mohammad Foroughmand, Hamid Galehdari, Mina Rasouli, Gholamreza Mohammadian and Mansour Mohammadi, 2008. Novel Mutation in the EXT-1 Gene in an Iranian Family Affected with Hereditary Multiple Exostoses. Pakistan Journal of Biological Sciences, 11: 1037-1041.