Broken silence: 22,841 predicted deleterious synonymous variants identified in the human exome through computational analysis

Synonymous single nucleotide variants (sSNVs) do not alter the primary structure of a protein, thus it was previously accepted that they were neutral. Recently, several studies demonstrated their significance to a range of diseases. Still, variant prioritization strategies lack focus on sSNVs. Here, we identified 22,841 deleterious synonymous variants in 125,748 human exomes using two in silico predictors (SilVA and CADD). While 98.2% of synonymous variants are classified as neutral, 1.8% are predicted to be deleterious, yielding an average of 9.82 neutral and 0.18 deleterious sSNVs per exome. Further investigation of prediction features via Heterogeneous Ensemble Feature Selection revealed that impact on amino acid sequence and conservation carry the most weight for a deleterious prediction. Thirty nine detrimental sSNVs are not rare and are located on disease associated genes. Ten distinct putatively non-deleterious sSNVs are likely to be under positive selection in the North-Western European and East Asian populations. Taken together our analysis gives voice to the so-called silent mutations as we propose a robust framework for evaluating the deleteriousness of sSNVs in variant prioritization studies.

Long-term clinical outcome of dental implants: A retrospective clinical study with a minimum follow-up between 9.5 and 17.7 years

The aim of this retrospective case series was to evaluate the clinical and radiographic outcomes of the patients that underwent implant surgery in all indication classes, with a follow-up of at least 9 years. 121 healthy patients in need for oral rehabilitation with dental implants were included in this study. 196 implants (160 conical, 73 cylindric design implants) were inserted. The implant survival rate was the primary outcome. Intra- and postoperative complications were additional criteria for success. The mean follow-up of the patients was 12.29 years (SD 1.39). Mean age of the study population was 51.0 years (SD 12.7). The mean bone loss around implants after at least 9 years of loading was measured as 2.0 mm (SD 0.73 mm). Intra-operative complications were seen in 5 patients. Post-operative complications included: 5 mucositis,1 dehiscence, 2 screw loosening, 1 infection at site and 1 nonintegrated implant. Two implants were lost in two patients. The overall implant survival rate was 99.1%. As a conclusion, oral rehabilitation with dental implant-supported prostheses can be accepted as a safe procedure with relevantly high survival rates of oral implants and successful aesthetic and functional outcomes.