Gene
TTC21A
tetratricopeptide repeat domain 21A
- HGNC 30761(opens in a new tab)
- Ensembl gene ENSG00000168026(opens in a new tab)
- NCBI Gene 199223(opens in a new tab)
Summary
- Cytogenetic location
- 3p22.2
- Coordinates
- Chromosome 3: 39,107,680–39,138,900 (GRCh38)
- Exons
- 29 exons across 31.2 kb
- Protein
- 1,313 amino acids
- Also known as
- STI2, IFT139A, Thm2
- MANE Select transcript
- ENST00000683103.1NM_001366900.1
- Locus type
- gene with protein product
- Very high
- Confident
- Low
- Very low
Reference genomeGRCh38hg38
Positions on gene and variant pages follow this choice, in this browser.
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Male Infertility
The inability of the male to effect fertilization of an ovum after a specified period of unprotected intercourse. Male sterility is permanent infertility.
- 1 GenCC submitter rates it definitive or strong
How TTC21A is laid out
- Coding sequence
- Untranslated region
- Intron
- Direction of transcription
Exons of the gene's MANE Select transcript (release v1.5), from NCBI and EMBL-EBI, on the GRCh38 reference genome.
Chromosome bands from UCSC's GRCh38 ideogram (2022-10-29).
Nearby genes from Ensembl release 116, on GRCh38.
Exons make up 4.2 kb of the gene's 31.2 kb; 3,942 of those bases code for the protein.
How a genome test reads TTC21A
4
positions in TTC21A where ClinVar classes a change as pathogenic or likely pathogenic
None of them falls in a region short reads find hard.
A whole genome covers all 31.2 kb of TTC21A, introns included, not only the 4.2 kb of exons.
External links
Gene records
Transcript
Protein
Where this comes from
- HGNC: the gene's symbol, name, other symbols and location.
- MANE Select v1.5, from NCBI and EMBL-EBI: the transcript, its exons and coding sequence.
- GenCC and ClinGen, released 2026-10-16: which conditions the gene is linked to, and how strongly.
- The ACMG secondary findings list, SF v3.2.
- ClinVar and the GIAB stratifications: known disease-causing sites, and the regions short reads find hard.
- Data release 2026.10.16-c6eea6bf.
Cite this page
Dante Labs. (n.d.). TTC21A gene: tetratricopeptide repeat domain 21A. Retrieved 17 October 2026, from https://dantelabs.com/genes/ttc21a
Dante Labs. TTC21A gene: tetratricopeptide repeat domain 21A [Internet]. [cited 17 October 2026]. Available from: https://dantelabs.com/genes/ttc21a
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