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Gene

AFF2

ALF transcription elongation factor 2

Summary

Cytogenetic location
Xq28
Coordinates
Chromosome X: 148,500,617–149,000,663 (GRCh38)
Exons
21 exons across 500 kb
Protein
1,311 amino acids
Also known as
FRAXE
Previous symbols
FMR2
MANE Select transcript
ENST00000370460.7NM_002025.4
Locus type
gene with protein product
  • Very high
  • Confident
  • Low
  • Very low

Reference genomeGRCh38

Positions on gene and variant pages follow this choice, in this browser.

Curated report relevant to this gene

    • Intellectual Disability

      • One of 233 genes linked to it

        • ClinGen rates the link definitive
        • 4 GenCC submitters rate it definitive or strong

    How AFF2 is laid out

    • Coding sequence
    • Untranslated region
    • Intron
    • Direction of transcription
    • Known disease-causing sites
    • Stretches short reads find hard
    Chromosome X, with a bracket where AFF2 sits. AFF2 and 4 genes near it on chromosome X, from 148,000,570 to 149,500,710.Chromosome XXq28p22.33p22.32p22.31p22.2p22.13p22.12p22.11p21.3p21.2p21.1p11.4p11.3p11.23p11.22p11.21p11.1q11.1q11.2q12q13.1q13.2q13.3q21.1q21.2q21.31q21.32q21.33q22.1q22.2q22.3q23q24q25q26.1q26.2q26.3q27.1q27.2q27.3q28148.2 Mb148.4 Mb148.6 Mb148.8 Mb149 Mb149.2 Mb149.4 MbFMR1NB: 147,981,235–148,026,665, forward strandFMR1NBAFF2: 148,500,617–149,000,663, forward strandAFF2: 149,414,877–149,415,506, reverse strandIDS: 149,476,988–149,521,096, reverse strandIDS: 149,477,104–149,540,926, reverse strandDiagram of AFF2: 21 exons on the forward strand of chromosome XExon 2: 1 known disease-causing siteExon 3: 4 known disease-causing sitesExon 6: 1 known disease-causing siteExon 11: 3 known disease-causing sitesExon 13: 2 known disease-causing sitesExon 14: 1 known disease-causing siteExon 15: 1 known disease-causing siteExon 18: 1 known disease-causing siteExon 19: 1 known disease-causing siteExon 1: 148,500,617–148,501,144, 528 basesExon 2: 148,651,999–148,652,131, 133 basesExon 3: 148,661,908–148,662,768, 861 basesExon 4: 148,809,876–148,809,920, 45 basesExon 5: 148,837,647–148,837,733, 87 basesExon 6: 148,842,966–148,843,002, 37 basesExon 7: 148,843,382–148,843,433, 52 basesExon 8: 148,885,889–148,885,985, 97 basesExon 9: 148,904,221–148,904,258, 38 basesExon 10: 148,953,580–148,953,739, 160 basesExon 11: 148,955,603–148,956,613, 1,011 basesExon 12: 148,958,337–148,958,458, 122 basesExon 13: 148,962,715–148,962,937, 223 basesExon 14: 148,966,790–148,967,079, 290 basesExon 15: 148,967,629–148,967,692, 64 basesExon 16: 148,973,471–148,973,607, 137 basesExon 17: 148,977,933–148,978,004, 72 basesExon 18: 148,978,362–148,978,455, 94 basesExon 19: 148,980,738–148,980,790, 53 basesExon 20: 148,987,367–148,987,557, 191 basesExon 21: 148,991,211–149,000,663, 9,453 bases1215′3′

    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 13.7 kb of the gene's 500 kb; 3,936 of those bases code for the protein.

    How a genome test reads AFF2

    17

    positions in AFF2 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 500 kb of AFF2, introns included, not only the 13.7 kb of exons.

    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.
    • The Human Phenotype Ontology, release 2026-09-01: the traits linked to the gene. Find out more at hpo.jax.org.
    • Data release 2026.10.16-c6eea6bf.

    Cite this page

    APA

    Dante Labs. (n.d.). AFF2 gene: ALF transcription elongation factor 2. Retrieved 17 October 2026, from https://dantelabs.com/genes/aff2

    Vancouver

    Dante Labs. AFF2 gene: ALF transcription elongation factor 2 [Internet]. [cited 17 October 2026]. Available from: https://dantelabs.com/genes/aff2

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