1. Genes and Genomic Entities
  2. TOP3A

TOP3A

DNA topoisomerase III alpha
OMIM: 601243, Gene2Phenotype

9 panels

Panel Reviews Mode of inheritance Details
9 panels
Green TOP3A in Mitochondrial DNA maintenance disorder


Level 2: Mitochondrial
Version 3.9
Latest signed off version: v3.0 (22 Mar 2023)

review BIALLELIC, autosomal or pseudoautosomal
Sources
  • Expert Review Green
  • NHS GMS
Phenotypes
  • ?Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 5, 618098
Green TOP3A in Severe microcephaly


Level 2: Neurology
Version 9.3
Latest signed off version: v9.0 (6 May 2026)

review BIALLELIC, autosomal or pseudoautosomal
Sources
  • NHS GMS
  • Expert Review Green
  • Literature
Phenotypes
  • Bloom Syndrome-like Disorder
Green TOP3A in Confirmed Fanconi anaemia or Bloom syndrome


Level 2: Haematology
Version 2.14
Latest signed off version: v2.5 (1 May 2024)

review BIALLELIC, autosomal or pseudoautosomal
Sources
  • North West GLH
  • Yorkshire and North East GLH
  • NHS GMS
  • Expert Review Green
  • Wessex and West Midlands GLH
Phenotypes
  • Microcephaly, growth restriction, and increased sister chromatid exchange 2
  • 618097 MGRISCE2 (Bloom-like syndrome)
  • MGRISCE2 (Bloom-like syndrome) 618097
Green TOP3A in Likely inborn error of metabolism


Level 2: Metabolic
Version 9.4
Latest signed off version: v9.0 (6 May 2026)

Component of the following Super Panels:

  • Childhood onset leukodystrophy
  • Hypotonic infant
  • Paediatric disorders
  • Unexplained death in infancy and sudden unexplained death in childhood

    		•  review BIALLELIC, autosomal or pseudoautosomal
    Sources
    • Expert Review Green
    • Expert Review Green
    • NHS GMS
    • Expert list
    Phenotypes
    • ?Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 5, 618098
    Green TOP3A in Possible mitochondrial disorder - nuclear genes


    Level 2: Mitochondrial
    Version 5.4
    Latest signed off version: v5.0 (6 May 2026)

    		review BIALLELIC, autosomal or pseudoautosomal
    Sources
    • Expert Review Green
    • NHS GMS
    Phenotypes
    • ?Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 5, 618098
    Green TOP3A in Fetal anomalies


    Level 2: Fetal (including NIPD)
    Version 7.10
    Latest signed off version: v7.0 (6 May 2026)

    		review BIALLELIC, autosomal or pseudoautosomal
    Sources
    • Expert Review Green
    • DD-Gene2Phenotype
    Phenotypes
    • Bloom Syndrome like Disorder
    Green TOP3A in DDG2P


    Version 7.1
    Latest signed off version: v7.0 (6 May 2026)

    Component of the following Super Panels:

  • Paediatric disorders

    		•  review BIALLELIC, autosomal or pseudoautosomal
    Sources
    • Expert Review Green
    • DD-Gene2Phenotype
    Phenotypes
    • Bloom Syndrome like Disorder
    Green TOP3A in Mitochondrial disorders


    Level 2: Mitochondrial
    Version 10.4
    Latest signed off version: v10.0 (6 May 2026)

    Component of the following Super Panels:

  • Childhood onset leukodystrophy

    		•  review BIALLELIC, autosomal or pseudoautosomal
    Sources
    • Expert Review Green
    • NHS GMS
    • Expert list
    Phenotypes
    • ?Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 5, 618098
    Green TOP3A in Monogenic short stature


    Level 2: Endocrinology
    Version 2.1
    Latest signed off version: v2.0 (6 May 2026)

    		review BIALLELIC, autosomal or pseudoautosomal
    Sources
    • Expert Review Green
    Phenotypes
    • Microcephaly, growth restriction, and increased sister chromatid exchange 2, OMIM:618097