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Genes & Genomes
Genes & Genomes
What can we help you with?
How do I obtain a transcript and protein sequence for a gene by using the NCBI Gene database?
Why do I see square brackets around some organism names in the NCBI Taxonomy database?
What was the reason for the removal of a prokaryotic RefSeq protein record and how do I find its replacement at NCBI?
How are genome assemblies generated and what are assembly levels?
What is genome annotation?
What types of genomic sequences are archived in the NCBI Nucleotide database for an organism?
How do I obtain subsets of the human proteome at NCBI?
How do I locate a RefSeq or UniProtKB (Swiss-Prot) sequence that is identical to my protein of interest at NCBI?
How do I use Gene records at NCBI to find and download all SNPs that are associated with a human gene?
Is there a whole genome sequence for my organism of interest at NCBI?
How do I use Gene records at NCBI to access human variation data in Variation Viewer?
How do I find the complete taxonomic lineage for an organism at NCBI?
How do I access all sequence records for a genome assembly on the NCBI web?
When I search your database for a gene, I obtain too many records. What sequence record should I choose?
How do I obtain a genomic sequence record for a gene using the NCBI Gene database?
How do I find variation information and associated phenotypes for a human gene at NCBI?
How do I find specific gene expression studies at NCBI?
What are the data sources for the expression displays on the Genome Data Viewer at NCBI?
How are organisms in the NCBI Taxonomy database formally named?
What are the sources of the NCBI Protein database sequences?
How can I compare expression of a gene of interest between different tissues at NCBI?
How can I find tissue-specific expression data for a gene of interest at NCBI?
How do I obtain a curated set of proteins for my organism or taxonomic group at NCBI?
What is the number of the NCBI Protein database records and does each record represent a unique sequence?
What are accession numbers at NCBI?
What are NCBI Reference Sequence (RefSeq) accession numbers and what information is embedded in their format?
How are GenBank protein sequences determined?
How do I obtain the current human proteome sequences from NCBI?
What are NCBI Assembly accession numbers?
How do I search NCBI Protein database for sequences that belong to a protein family?
Where and how do I retrieve human mitochondrial genome sequences, including those from human genealogy studies?
On what sequences do you base NCBI Taxonomy classification and the Taxonomy Common Tree?
How do I find GenBank records annotated with variation features?
What is a genome assembly?
Why are genomes sequenced?
Who generates genome assemblies that are present in the NCBI databases?
How does NCBI process submitted genome assemblies and where can I find these?
What are reference and representative genomes and how do I find these at NCBI?
How do I access information on genomic clones at NCBI?
What are genomic-clone libraries and how are they made?
What does 'genomic clone has been placed' really mean?