Welcome to NCBI's Sequence Viewer 3.50.0

To get started, or review the help documentation.

Human chromosome: NC_000001: This link provides a look at human chromosome 1. There are two panels shown by default: an overview panel showing the density of annotated genes along with a select number of genes for reference; and a zoomed in graphical view showing a region of the chromosome itself.
Human reference genomic region: NG_000007: This link shows a reference genomic region − that is, a genomic region that has undergone substantial curation by staff at NCBI. This particular record shows the beta globin locus on chromosome 11. Two panels are shown by default: an overview panel showing the density of annotated genes along with a select number of genes for reference; and a zoomed in graphical view showing individual features on the record.
MGC mRNA: BC066124.1: This link shows a sample mRNA sequence from the Mammalian Genome Collection. This link will open with two views by default: a graphical panel showing the feature annotation on the sequence; and a sequence panel providing the bases of the sequence itself.
Viral genome: AC_000020, sequence viewport and marker: This link provides an example of how a viral genome can be shown. The link will open with three panels (an overview graphical panel; a zoomed in graphical panel; and a sequence panel); additionally, a marker is set at position 800.

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