Fibrodysplasia ossificans progressiva

Researchers have associated a gene region, 4q27-31, on chromosome 4 to a severe disorder known as Fibrodysplasia ossificans progressiva (FOP). FOP is a rare disorder that is characterised by ongoing postnatal heterotopic ossification. Postnatal meaning after birth, heterotopic meaning abnormal anatomical conditions and ossification is defined as the transformation of soft tissue into bone tissue. When soft tissues are damaged they become ossified and this causes joints to be frozen permanently in place. There is no known cure for the debilitating disease. FOP is caused by spontaneous mutations in gametes and the allele has a high variability and complete penetrance. The spontaneous mutation causes injury sites to express an enzyme for bone repair in a malfunctioned state, hence there is excess bone morphogenetic protein 4 (BMP4).
Scientists were looking to identify the location of the gene. Researchers conducted an analysis of genomewide linkage by using four different families affected by the disorder. The PCR process was used to magnify the microsatellite markers that cover human autosomes. Genetic mapping was also used to determine the location of the gene. It was found that the FOP phenotype was linked to the 4q27-31 region on the 4th chromosome. This was associated with crossover events in meiosis and the researchers discovered that the FOP gene was within a 36cM between proximally by D4S1625 and distally by D4S2417. Within this interval it was determined that there was at least one gene involved in the bone morphogenetic protein-signalling pathways.
This study was important because the region where the active gene was located was discovered. By finding the region where the gene is active on the chromosome, scientists are able to do further studies into how to target the gene that affects the functions of the body. It may help scientists target and turn off the enzyme that creates BMP4 which is produced in bone repair.

JihHui Tseng - 42031451

http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=10631143