Most of the mutations, which cause diseases and could be identified by science, was found out in the exome areas. While most of the genetic tests, which have been applied so far, have been screening only one gene or a few genes that considered to be related to the disease, WES tests screens thousands of genes simultaneously.
This feature makes WES one of the most effective methods for revealing out the reasons of complex genetic problems. WES is ideal for finding out new mutations and atypical findings of the disease.
All of the exomes in the human genome can screen with whole-exome sequencing.
Particularly, exome sequencing is very important in establishing the final diagnosis of the patient's disease, which is not clinically diagnosed yet. Establishing the final diagnosis of the disease with the mutation is important in genetic disease carrier families for the healthy posterity. Moreover, identification of the gene that is responsible for the disease allows us to identify whether the fetus is sick in the new pregnancies of the families already having sick children, and also allows us to prevent the disease with the genetic examination in the Vitro fertilization stage.
Less than 2% of the human genome corresponds to the protein-coding genes; this means ~200,000 exomes of the approximately 50 mb reciprocal coupled 21,000 genes. The function of the remaining genomes is not known to a large extent. The areas having coding potential are generally named as "exome". A great majority of the disease-causing mutations, which are identified so far and inherited by birth, are located in this little coding area. Approximately 85% of these disease-causing mutations in Mendelian disorders are in this coded exomes.
As distinct from all other exome tests, genetic materials belonging to the mother, father and the sick child, if there is, are taken into examination simultaneously. By these means, the mutation type belonging to the family among the revealed changes after sequencing is reported by matching them with the information coming from mother and father. Through these triple analysis, the genetic disease that the family carries can reveal more healthy.