Achondroplasia (from the Greek for "without cartilage growth") is a condition that results in dwarfism. It is caused by a mutation in the FGFR3 (fibroblast growth factor receptor 3) gene. The FGFR3 gene is located on the short arm of chromosome 4 at position 16.3. This "achondroplasia location" on chromosome 4 can affect the gene's ability to direct the proper development and maintenance of bone.
(Click FGFR3 Gene for more detailed information on how a defect in this gene can lead to achondroplasia. This article also discusses the role of FGFR3 in other conditions, such as bladder cancer.)