A team of scientists from Scripps Research has created a genomic technique that facilitates the study of rare diseases. The technique serves in fact to trace the causes, comparing the activity of the maternal and paternal alleles. When levels fall out of the normal range, they insert the allele into the possible causes of the disease. This allows you to narrow the circle and facilitate analysis.
The researchers were looking for a way to identify rare genetic diseases, especially those with early appearance. Standard sequencing methods identify already known genetic mutations, which cause protein deficits. At least half of rare genetic diseases, however, have much more subtle causes. For example, traditional sequencing does not see mutations affecting regions of DNA but not genes.
This is a big problem, as these regions regulate the way genes work. When they do not work properly, the activities of the genes change accordingly and the diseases are manifested. Still, they are invisible mutations for traditional tests. At conception, we inherit a set of maternal alleles and a paternal set. In order for a genetic disease to manifest itself, it is almost always necessary that the anomaly is present in both alleles.
This does not apply to many rare genetic diseases, which also occur with only one anomalous allele. To identify them, the team analyzed the activities of all pairs of alleles. Couples with a strong gradient between one allele and the other are the probable causes of the disease. To test the technique, the researchers used it on patients suffering from rare muscular dystrophies. Thanks to the methodology, they identified all areas of DNA related to the disease. Now the goal is to use the technique on risky newborns, so as to intervene as soon as possible against the disease.
Source: scripps.edu