ACMG: Technical standard on CFTR variant testing updated

Reviewed by Emily Henderson, B.Sc.May 14 2020

It has been nearly two decades since the American College of Medical Genetics and Genomics (ACMG), together with the American College of Obstetricians and Gynecologists, made the landmark recommendation that cystic fibrosis (CF) become the first target of pan-ethnic universal carrier screening, with ACMG identifying a core panel of 23 pathogenic variants to be tested. Now, with the widespread availability and decreased cost of next-generation sequencing, it is possible to more easily interrogate all regions of the CFTR gene and correlate variants with phenotypes. This ability to move beyond targeted molecular testing methods for routine CF screening and diagnosis led to the ACMG Laboratory Quality Assurance Committee's release of a new key document: "CFTR Variant Testing: A Technical Standard of the American College of Medical Genetics and Genomics (ACMG)," published in ACMG's official journal, Genetics in Medicine.

This technical standard includes revised information about CF and the CFTR gene, new testing considerations and methodologies, and updated recommendations for the interpretation and reporting of test results. Written in clearly delineated sections, this important new resource will become a well-used reference by molecular genetics laboratories everywhere.

Now that CF screening and diagnosis are established tests and next-generation sequencing is an established method in many clinical genetics laboratories, the ACMG wanted to update its technical laboratory standards for CFTR variant testing so that they would not only better reflect current laboratory practices but would also better enable future advancements in the field. Though it wasn't originally planned, it seems appropriate to have these updated ACMG standards published in May since May is also National Cystic Fibrosis Awareness Month."

Josh Deignan, PhD, FACMG, lead author

The new ACMG document includes detailed sections on What to Test, How to Test and What to Report regarding CFTR variant testing.