Researchers from the Mount Sinai Medical Center hospital analyzed the genomes of half a million people and found about ten healthy people with a mutated gene, which inevitably had to lead to a fatal disease.
The reasons of health stability in the presence of mutations are still unknown. The study has been published in the Nature Biotechnology journal.
The scientists have studied the genetic information in about 590 thousand people to reveal those who demonstrate a healthy phenotype in the presence of mutant genes associated with one of 584 severe genetic disorders. 874 of genes, which are characterized by a complete penetrance, were verified and mutations occur in 100% of cases.
The geneticists also checked that people who were examined really do not show any symptoms of the disease.
The analysis revealed 13 people who were completely resistant to one of eight genetic mutations despite the fact that it had been previously considered impossible. One of such mutations causes cystic fibrosis – a serious and incurable disease, which leads to respiratory function violations.
The investigators also emphasize that genetic testing is usually limited to the patients who show the symptoms of disease, as well as their family members. Such an approach may help to ensure that silent mutations of a small number of people would go unnoticed.
Geneticists have so far failed to obtain consent from individuals for the further research; therefore, the mechanisms responsible for resistance are unknown. However, the scientists believe that factors that mediate the effects of highly penetrant mutations play the role here. Their research could help in the creation of effective purposeful therapy.