The European Society
of Human Genetics

Stepwise ABC system variant classification of any type of genetic variant

Stepwise ABC system variant classification of any type of genetic variant

Update: The most recent version (version 2.0) of the ABC system has been added after publication of an Open Access article in Eur J Hum Genet comparing ACMG/AMP and ABC classification of 10 challenging cases, see PMID 38778080 or https://www.nature.com/articles/s41431-024-01617-8. An updated .pptx presentation of the ABC system and the comparison article has been added as well.

Update: The article about the ABC system for variant classification has been accessed more than 10 000 times since E-pub date in EJHG, and after user feedback the standardized variant comments (step C) has been updated, see link link below to an improved and updated system presentation below (pptx-file).

An ad hoc working group in ESHG proposed a two-dimensional system for variant classification two years ago, and this work has now progressend and resulted in the so-called ABC system: A stepwise approach to variant classification that can be used independently or as an add-on to the ACMG system. See Figure 2 for schematics.

A link to the Open Access article describing the system: https://rdcu.be/ckvP5

Attached you will find the manuscript .pdf and a .pptx file of all the figures and tables (in colours).

Hopefully this new system will make variant classification easier, more informative and of better consistency and clinical usefulness. We welcome feedback and suggestions for improvements!

Best regards

Gunnar D Houge