MKKS and Bardet-Biedl syndrome: The combination of several genetic approaches allowed us to confirm the molecular diagnosis of five BBS patients whereby seven predicted pathogenic variants, some of them novel, were found in three BBS genes: BBS1, BBS5 and BBS6. While BBS1 is the most frequently mutated gene in BBS, accounting for 23% of cases and 15% of the total mutational load10,26, BBS5 represents a minor contributor, with only 2% of cases.