WES or CES: some recommendations

What should you check before ordering CES or WES at any lab?

1. Ask the lab if they really do Whole Exome Sequencing or Clinical Exome Sequencing. By doing WES, all (all!) the genes of the genome are sequenced. Therefore any lab offering exome sequencing without explicitly doing all genes will very likely perform just CES.

2. Guessing if it’s CES or WES from the price. The technical costs of doing Clinical Exome Sequencing (CES) aren’t usually above 900 € (lab costs only, bioinformatics and medical report excluded). Therefore make sure that any lab offering exome sequencing for several thousands of euros is actually doing WES and not CES. A WES analysis with a good level of coverage (minimum 50x) can run in terms of lab costs well beyond 2,000 €.

3. Ask for the level of coverage offered. Several labs today offer WES or CES with very low levels of coverage. The level of coverage is crucial for the quality of the results and therefore for the interest of the patients. Unfortunately it is also extremely relevant for the total expenses of the run. The cost of the same type of genetic analysis done at different levels of coverage is dramatically different, as it may double or even triple. Therefore we recommend requesting specific information on the coverage offered. In general, we do not rate as acceptable any coverage below 50x (especially for WES). For CES Breda Genetics always does 100x.