An international team of scientists based at St George Hospital has made an important breakthrough in identifying the gene responsible for a wide range of debilitating birth defects.
A team of medical scientists, headed by St George Hospital scientist Dr Raymond Clarke, has screened more than 150 affected individuals and families from Australia and around the world.
Dr Clarke said that DNA samples were taken for genetic testing over a seven year period and in 2007 mutations were found within a gene known to scientists as GDF6.
“The GDF6 gene is a special growth factor which determines where and when cartilage is formed in the developing embryo,” Dr Clarke said.
“This gene appears to be essential for the normal formation of spinal discs as well as cartilages in the ears that control hearing and cartilages and bones in the mouth, hands and feet,” he said.
Dr Clarke said that it still remained a puzzle why GDF6 mutations cause birth defects of the heart, kidney and nerves.
Newborn infants may be born with abnormalities of the spine, face, mouth, hearing, nerves, heart or kidney, and this rare combination of birth defects – known as Klippel-Feil Syndrome (KFS) – can result in life-long disabilities.
“Scientists identified gene mutations in patients by comparisons with the human gene map recently completed by a world-wide consortium of scientists,” Dr Clarke said.
“Research showed that not only were identical mutations in the GDF6 gene present in unrelated patients from different countries, but the mutations were present in a number of large families – and only in those members of the family which had birth defects.
“It has been found that the GDF6 gene has a particularly important role in the formation of spinal discs located between the vertebrae. These discs provide essential flexibility and protection for the spinal cord, similar to the shock-absorbers in a car,” he said.
Key scientist, Dr Zhi Ming Fang said that GDF6 mutations result in abnormal formation and degeneration of cartilage and bone and that studies are now underway to reverse these processes.
As disc generation is wide spread within the community, particularly in the elderly, it is hoped that genetic medicines like GDF6 will one day be available for rehabilitation of the joints.