@article {873, title = {A variant-centric perspective on geographic patterns of human allele frequency variation.}, journal = {Elife}, volume = {9}, year = {2020}, month = {2020 12 22}, abstract = {

A key challenge in human genetics is to understand the geographic distribution of human genetic variation. Often genetic variation is described by showing relationships among populations or individuals, drawing inferences over many variants. Here, we introduce an alternative representation of genetic variation that reveals the relative abundance of different allele frequency patterns. This approach allows viewers to easily see several features of human genetic structure: (1) most variants are rare and geographically localized, (2) variants that are common in a single geographic region are more likely to be shared across the globe than to be private to that region, and (3) where two individuals differ, it is most often due to variants that are found globally, regardless of whether the individuals are from the same region or different regions. Our variant-centric visualization clarifies the geographic patterns of human variation and can help address misconceptions about genetic differentiation among populations.

}, keywords = {Gene Frequency, Genetic Variation, Genetics, Population, Geography, Humans}, issn = {2050-084X}, doi = {10.7554/eLife.60107}, author = {Biddanda, Arjun and Rice, Daniel P and Novembre, John} } @article {735, title = {Detailed genetic characteristics of an international large cohort of patients with Stargardt disease: ProgStar study report 8.}, journal = {Br J Ophthalmol}, volume = {103}, year = {2019}, month = {2019 03}, pages = {390-397}, abstract = {

BACKGROUND/AIMS: To describe the genetic characteristics of the cohort enrolled in the international multicentre progression of Stargardt disease~1 (STGD1) studies (ProgStar) and to~determine geographic differences based on the allele frequency.

METHODS: 345 participants with a clinical diagnosis of STGD1 and harbouring at least one disease-causing ABCA4 variant were enrolled from 9 centres in the USA and Europe. All variants were reviewed and analysis was performed including allele frequency in public databases and pathogenicity predictions. Participants with multiple likely pathogenic variants were classified into four national subgroups (USA, UK, France, Germany), with subsequent comparison analysis of the allele frequency for each prevalent allele.

RESULTS: 211 likely pathogenic variants were identified in the total cohort, including missense (63\%), splice site alteration (18\%), stop (9\%) and others. 50 variants were novel. Exclusively missense variants were detected in 139 (50\%) of 279 patients with multiple pathogenic variants. The three most prevalent variants of these patients with multiple pathogenic variants were p.G1961E (15\%), p.G863A (7\%)~and~c.5461-10 T>C (5\%). Subgroup analysis revealed a statistically significant difference between the four recruiting nations in the allele frequency of nine variants.

CONCLUSIONS: There is a large spectrum of ABCA4 sequence variants, including 50 novel variants, in a well-characterised cohort thereby further adding to the unique allelic heterogeneity in STGD1. Approximately half of the cohort harbours missense variants only, indicating a relatively mild phenotype of the ProgStar cohort. There are significant differences in allele frequencies between nations, although the three most prevalent variants are shared as frequent variants.

}, keywords = {Adolescent, Adult, Age of Onset, Aged, ATP-Binding Cassette Transporters, Child, Child, Preschool, Cohort Studies, Databases, Factual, DNA Mutational Analysis, Female, Gene Frequency, Genotyping Techniques, Geography, Humans, Internationality, Macular Degeneration, Male, Middle Aged, Mutation, Polymerase Chain Reaction}, issn = {1468-2079}, doi = {10.1136/bjophthalmol-2018-312064}, author = {Fujinami, Kaoru and Strauss, Rupert W and Chiang, John Pei-Wen and Audo, Isabelle S and Bernstein, Paul S and Birch, David G and Bomotti, Samantha M and Cideciyan, Artur V and Ervin, Ann-Margret and Marino, Meghan J and Sahel, Jos{\'e}-Alain and Mohand-Said, Saddek and Sunness, Janet S and Traboulsi, Elias I and West, Sheila and Wojciechowski, Robert and Zrenner, Eberhart and Michaelides, Michel and Scholl, Hendrik P N} }