2/ The way you approach this problem will depend on if you are starting with a #gene of interest or if you already have the ID (e.g rs699) of a variant for which you want to find the observed allele frequencies.
3/ If you are starting with a gene, search for the gene name or ID from the #Ensembl homepage and navigate to the Gene tab.
4/ Now, click on ‘Variant table’ in the menu on the left hand side of the page to view all short sequence variants found within the gene.
5/ Among lots of other #data, there is a column called ‘Global MAF’. This column will report the Minor Allele Frequency (MAF) observed for this variant in the @1000genomes project, if available.
6/ You can filter the table based on the MAF to show variants with commonly or rarely observed minor alleles. Just click on the blue ‘Global MAF’ button in the Filter section above the table and drag the slider to choose the MAF range to want to see.
7/ ⚠️ Warning ⚠️ This will also remove all variants with no MAF reported from the table.
8/ Now, click on the ID of the variant within the table to navigate to the Variant tab to find out more. Alternatively, if you already know the ID of your variant of interest (e.g rs699), you can search for the variant ID from the homepage.
9/ Now that we’re in the variant tab, click on ‘Population genetics’ to navigate to a page showing observed allele frequencies for different populations across a number of different projects. The data is presented as pie charts and in tabular form as well.
10/ For human 🧑🤝🧑, Ensembl presents allele frequencies from the @1000genomes, @gnomad_project, @NCBI ALFA project, GEM-J project, GGVP, @nih_nhlbi Exome sequencing project, TOPMed and UK10K projects:
11/ Scroll down to see all of the data available for your variant!
12/ Click on ‘Sub-populations’ to see observed allele frequencies in the individual populations that make up the continental populations.
13/ The table shows allele frequencies for each individual population on the left (remember each person sequenced in the projects contributes 2 allele counts as humans are diploid!) and genotype frequencies on the right (homo- or heterozygous)
14/ Click on ‘Show’ in the Genotypes column in the table to jump to a table showing you the observed genotype for each individual. You can use the sample ID to order cell lines derived from each individual in the @1000genomes project from the @Coriell_Science cell repository
Want to learn about a gene function, but there’s no functional data in your species of interest? Or maybe looking for a homologue of your fav gene in a model organism to carry out functional work? Look no further! This #tweetorial will show you how to find orthologues in @ensembl
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Let’s start on the Ensembl homepage and search for our #gene of interest SCP2 by typing its name into the search box. Then go to the gene tab by clicking on the gene name in the search results.
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You can learn more about the #gene function by exploring gene ontology terms and associated phenotypes. Let’s click on Phenotypes in the side menu. This view shows phenotypes associated with our gene of interest and variants in this gene.