Lluis Quintana-Murci, Antoine Favier, Franck Rapaport, David Neil Cooper, Peter D. Stenson, Etienne Patin, Laurent Abel, Jean-Laurent Casanova, Yufei Luo, Marie Lopez, Antonio Rausell, Yoann Seeleuthner, The Clinical Bioinformatics laboratory (Equipe Inserm U1163), Imagine - Institut des maladies génétiques (IHU) (Imagine - U1163), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Paris (UP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Paris (UP), Génétique Evolutive Humaine - Human Evolutionary Genetics, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Human genetics of infectious diseases: Complex predisposition (Equipe Inserm U1163), St. Giles Laboratory of Human Genetics of Infectious Diseases, Rockefeller University [New York], Institute of Medical Genetics, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK, Howard Hughes Medical Institute (HHMI), Chaire Génomique humaine et évolution, Collège de France (CdF (institution)), The Laboratory of Clinical Bioinformatics was supported by the French National Research Agency (ANR)'Investissements d’Avenir'Program (Grant ANR-10-IAHU-01) and Christian Dior Couture, Dior. The Laboratory of Human Geneticsof Infectious Diseases was supported, in part, by grants from ANR under the'Investissements d’Avenir'Program (Grant ANR-10-IAHU-01), the Fondation pourla Recherche Médicale (Equipe FRM EQU201903007798), the St. Giles Foundation,and the Rockefeller University. The laboratory of L.Q.-M. is supported by theInstitut Pasteur, the Collège de France, the French Government’s Investissementsd’Avenir program, Laboratoires d’Excellence'Integrative Biology of Emerging Infectious Diseases'(Grant ANR-10-LABX-62-IBEID) and'Milieu Intérieur'(GrantANR-10-LABX-69-22701), and the Fondation pour la Recherche Médicale (EquipeFRM DEQ20180339214). D.N.C. and P.D.S. acknowledge the financial supportof Qiagen Inc. through a license agreement with Cardiff University., ANR-10-IAHU-0001,Imagine,Institut Hospitalo-Universitaire Imagine(2010), ANR-10-LABX-0062,IBEID,Integrative Biology of Emerging Infectious Diseases(2010), ANR-10-LABX-0069,MILIEU INTERIEUR,GENETIC & ENVIRONMENTAL CONTROL OF IMMUNE PHENOTYPE VARIANCE: ESTABLISHING A PATH TOWARDS PERSONALIZED MEDICINE(2010), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris Cité (UPCité)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris Cité (UPCité), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Cardiff University, Collège de France - Chaire Génomique humaine et évolution, PATIN, Etienne, Instituts Hospitalo-Universitaires - Institut Hospitalo-Universitaire Imagine - - Imagine2010 - ANR-10-IAHU-0001 - IAHU - VALID, Integrative Biology of Emerging Infectious Diseases - - IBEID2010 - ANR-10-LABX-0062 - LABX - VALID, and Laboratoires d'excellence - GENETIC & ENVIRONMENTAL CONTROL OF IMMUNE PHENOTYPE VARIANCE: ESTABLISHING A PATH TOWARDS PERSONALIZED MEDICINE - - MILIEU INTERIEUR2010 - ANR-10-LABX-0069 - LABX - VALID
Humans homozygous or hemizygous for variants predicted to cause a loss of function of the corresponding protein do not necessarily present with overt clinical phenotypes. However, the set of effectively dispensable genes in the human genome has not yet been fully characterized. We report here 190 autosomal genes with 207 predicted loss-of-function variants, for which the frequency of homozygous individuals exceeds 1% in at least one human population from five major ancestry groups. No such genes were identified on the X and Y chromosomes. Manual curation revealed that 28 variants (15%) had been misannotated as loss-of-function, mainly due to linkage disequilibrium with different compensatory variants. Of the 179 remaining variants in 166 genes (0.82% of 20,232 genes), only 11 alleles in 11 genes had previously been confirmed experimentally to be loss-of-function. The set of 166 dispensable genes was enriched in olfactory receptor genes (41 genes), but depleted of genes expressed in a wide range of organs and in leukocytes. The 125 dispensable non-olfactory receptor genes displayed a relaxation of selective constraints both between species and within humans, consistent with greater redundancy. In total, 62 of these 125 genes were found to be dispensable in at least three human populations, suggesting possible evolution toward pseudogenes. Out of the 179 common loss-of-function variants, 72 could be tested for two neutrality selection statistics, and eight displayed robust signals of positive selection. These variants included the knownFUT2mutant allele conferring resistance to intestinal viruses and anAPOL3variant involved in resistance to parasitic infections. Finally, the 41 dispensable olfactory receptor genes also displayed a strong relaxation of selective constraints similar to that observed for the 341 non-dispensable olfactory receptor genes. Overall, the identification of 166 genes for which a sizeable proportion of humans are homozygous for predicted loss-of-function alleles reveals both redundancies and advantages of such deficiencies for human survival.Significance statementHuman genes homozygous for seemingly loss of function (LoF) variants are increasingly reported in a sizeable proportion of individuals without overt clinical phenotypes. Here, we found 166 genes with 179 predicted LoF variants for which the frequency of homozygous individuals exceeds 1% in at least one of the populations present in databases ExAC and gnomAD. This set of putatively dispensable genes showed relaxation of selective constraints suggesting that a large number of these genes are undergoing pseudogenization. Eight of the common LoF variants displayed robust signals of positive selection including two variants located in genes involved in resistance to infectious diseases. The identification of dispensable genes will allow identifying functions that are, at least nowadays, redundant, or possibly advantageous, for human survival.