Carrier DNA Tests for Mucolipidosis IV
Mucolipidosis IV
Unless you are of Ashkenazi Jewish descent or know someone who has mucolipidosis, you may never have heard of this neurodegenerative disorder which is identified by four different types and is sometimes confused with cerebral palsy when first diagnosed.
There is no cure for mucolipidosis IV. Those who do survive to adulthood have numerous impairments and a poor quality of life. They are generally treated with physical therapy, speech therapy, corneal transplant, iron supplements, and a variety of methods to try to alleviate their symptoms.
Scientists have been able to identify the gene responsible for the disease, which is defined by mutations of proteins in cells. Mucolipidosis IV occurs if a child inherits two copies of the defective gene, one from each parent. If both parents carry the defective gene, their child has one in four chances of developing the disease or one in two chances of receiving a defective gene.
Those who have only one defective gene are known as carriers. These individuals do not have any symptoms but they can pass the defective gene on to their children. It is estimated that about 1 person in 40,000 is afflicted and perhaps 1 in 90 are carriers.
Scientists are able to identify the defective gene through DNA testing and make an accurate diagnosis of mucolipidosis IV. They can screen for carriers or obtain information about the likelihood of passing on this genetic disorder through prenatal testing in about the 8th week of pregnancy.
Depending upon the type of insurance coverage and yearly deductible, screening can be very expensive. To reduce this cost one partner can be screened first, and if discovered to be a carrier the other can then be tested.
Although Ashkenazi Jews are most susceptible, the disorder is found in those of other ethnic backgrounds, but less frequently. Because of the severity of the disease, it is important to be tested for reproductive risk if there is a history of mucolipidosis IV in the family and a chance of transmitting it to the next generation.