Literature coverage and curation

A list of relevant publications was retrieved using pubmed.mineR [17] tool using country names to query for publications describing “mutation”, “variant” or “polymorphism”. An exhaustive list of PubMed IDs was retrieved for each of the 23 countries which have a significant number of Arabs. These include 22 countries which were part of the Arab League and speak Arab- Algeria, Bahrain, the Comoros Islands, Djibouti, Egypt, Iraq, Jordan, Kuwait, Lebanon, Libya, Morocco, Mauritania, Oman, Palestine, Qatar, Saudi Arabia, Somalia, Sudan, Syria, Tunisia, the United Arab Emirates, Yemen apart from Israel which has a significant number of Arabs [18–23].

Each of the full-text articles were retrieved and manually curated, to include an extensive array of information, including country of origin and ethnicity apart from the variant type, the methods used for the annotation of variants etc. Special emphasis was made on including only papers that described variants in the countries, and not just reported them.

Each of the variants were further normalised to the GRCh37/hg19 build version of the Human genome for the genomic location and variant position, as well as according to the Human Genome Variation Society (HGVS) nomenclature for the representation of the variants. Gene names were similarly normalised to the Human Gene Nomenclature Committee (HGNC) nomenclature using Mutalyzer tool [24] which check for consistency for the normalised variants. Wherever applicable, dbSNP IDs and ClinVar IDs were added for variants mapping to respective databases. The disease names were also normalised according to the annotations in the Online Mendelian Inheritance in Man (OMIM) [25–27] database and linked wherever they could be consistently mapped.

For each of the variants, additional information on the zygosity of variant, and the method or assay used for identification of the variant were also collected. To ease the annotation, a prefilled list of techniques was used as a drop-down. The entire activity was performed on a template available to all annotators through Google docs online as well as offline through templates in Microsoft Excel. The annotators individually filled in variants for each country. Along with the template, the annotators were also given tutorial slides to train themselves on the curation guidelines so as to maintain uniformity across all curators.