DNA Sequence Analysis Tool

Analyze nucleotide composition from NCBI sequences

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NCBI Accession Number

Or Upload Sequence File

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Supported formats: FASTA, plain text

Maximum file size: 20MB. For large datasets and commercial use, please contact priyam.jyotsna@gmail.com

Frequently Asked Questions

What is nucleotide composition analysis?

Nucleotide composition analysis is the process of determining the frequency and distribution of nucleotides (A, T, G, C for DNA; A, U, G, C for RNA) within a biological sequence. This analysis provides insights into the GC content, sequence bias, and structural characteristics of genetic material. The results can help identify functional regions, evolutionary patterns, and taxonomic relationships between organisms.

Why is GC content important in DNA analysis?

GC content (the percentage of guanine and cytosine bases) is an important parameter in molecular biology because it affects DNA stability, melting temperature, and gene expression. DNA with higher GC content forms stronger bonds due to the three hydrogen bonds between G and C (compared to two between A and T), making it more thermally stable. GC content varies across organisms, genomic regions, and can indicate horizontally transferred genes, CpG islands, or coding regions.

How do I find an NCBI accession number for my analysis?

NCBI accession numbers can be found by searching the NCBI databases like GenBank, RefSeq, or Nucleotide. Visit the NCBI website (www.ncbi.nlm.nih.gov) and search for your gene, organism, or sequence of interest. The accession number typically appears in the format of letters followed by numbers (e.g., NC_000001.11 for human chromosome 1). You can copy this accession number and paste it into our tool to retrieve and analyze the sequence.

What file formats are supported for uploading sequences?

Our tool supports FASTA format (.fasta, .fa) and plain text (.txt) files. The FASTA format begins with a description line starting with '>' followed by sequence data. Plain text files should contain only the sequence characters without any header. Both formats should contain valid nucleotide characters: A, T, G, C (for DNA) or A, U, G, C (for RNA). Other characters like N (any nucleotide) are also recognized but counted separately.

What is the maximum sequence size for analysis?

The tool can process sequences up to 20MB in size within the browser. For larger sequences, you'll be provided with a direct download link to retrieve the sequence from NCBI. Processing very large sequences in the browser may affect performance. If you regularly work with larger genomic sequences or need custom analysis, please contact us for specialized solutions tailored to your research needs.

How to Cite This Tool

APA Format

Priyam, J. (2025). Jyotsna's NCBI Tools - DNA Sequence Analysis Tool. DOI: 10.5281/zenodo.15069907

MLA Format

Priyam, J. "Jyotsna's NCBI Tools - DNA Sequence Analysis Tool." 2025, DOI: 10.5281/zenodo.15069907. Accessed April 26, 2025.

BibTeX Format

@software{10_5281_zenodo_15069907, author = {Priyam, J.}, title = {Jyotsna's NCBI Tools - DNA Sequence Analysis Tool}, year = {2025}, version = {1.0.0}, doi = {10.5281/zenodo.15069907}, url = {https://ncbi.jyotsnapriyam.com/dna-analysis}, note = {Accessed: April 26, 2025} }