The Spectrum of Protein Truncating Variants in European Breast Cancer Cases.

Germline protein truncating variants (PTVs) in the gene have been associated with a 2-4-fold increased breast cancer risk in case-control studies conducted in different European populations. However, the distribution and the frequency of PTVs in Europe have never been investigated. In the present study, we collected the data of 114 European female breast cancer cases with PTVs ascertained in 20 centers from 13 European countries. We identified 27 different PTVs. The p.Gln1701* PTV is the most common PTV in Northern Europe with a maximum frequency in Finland and a lower relative frequency in Southern Europe. On the contrary, p.Arg1931* seems to be the most common PTV in Southern Europe. We also showed that p.Arg658*, the third most common PTV, is more frequent in Central Europe, and p.Gln498Thrfs*7 is probably a founder variant from Lithuania. Of the 23 rare or unique PTVs, 15 have not been previously reported. We provide here the initial spectrum of PTVs in European breast cancer cases