Red cell disorders
Gene: TCN2EnsemblGeneIds (GRCh38): ENSG00000185339
EnsemblGeneIds (GRCh37): ENSG00000185339
OMIM: 613441, Gene2Phenotype
TCN2 is in 11 panels
1 review
Danielle Ariti (University of Melbourne)
26 pathogenic TCN2 variants have been reported in over 40 individuals; Bi-allelic (deletions, insertions, nonsense, mutations) variants have been reported; multiple mouse models
Transcobalamin II deficiency is characterised by early onset (infancy) failure to thrive, megaloblastic anaemia, immunodeficiency and pancytopaenia. Other features include methylmalonic aciduria, recurrent infections, hypogammaglobulinaemia, pallor, hypotonia and vomiting and diarrhoea. Treatment with cobalamin (B12) may be of clinical benefit, but left untreated may result in intellectual disability and neurologic abnormalities.Created: 8 Sep 2021, 11:53 p.m. | Last Modified: 8 Sep 2021, 11:53 p.m.
Panel Version: 0.75
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
Transcobalamin II deficiency MIM# 275350; Decreased Ig levels; Megaloblastic anaemia; pancytopaenia; Reticulocytopaenia; failure to thrive; diarrhoea; hypogammaglobulinaemia; pallor; hypotonia; respiratory infection; if untreated (B12) for prolonged periods results in intellectual disability
Publications
Details
- Mode of Inheritance
- BIALLELIC, autosomal or pseudoautosomal
- Sources
-
- Expert Review Green
- Yorkshire and North East GLH
- NHS GMS
- Wessex and West Midlands GLH
- North West GLH
- London South GLH
- Phenotypes
-
- Transcobalamin II deficiency MIM# 275350
- Decreased Ig levels
- Megaloblastic anaemia
- pancytopaenia
- Reticulocytopaenia
- failure to thrive
- diarrhoea
- hypogammaglobulinaemia
- pallor
- hypotonia
- respiratory infection
- if untreated (B12) for prolonged periods results in intellectual disability
- OMIM
- 613441
- Clinvar variants
- Variants in TCN2
- Penetrance
- None
- Publications
- Panels with this gene
History Filter Activity
Entity classified by Genomics England curator
Zornitza Stark (Victorian Clinical Genetics Services; Australian Genomics)Gene: tcn2 has been classified as Green List (High Evidence).
Set Phenotypes
Zornitza Stark (Victorian Clinical Genetics Services; Australian Genomics)Phenotypes for gene: TCN2 were changed from megaloblastic bone marrow; neutropenia; thrombocytopenia; 275350 Transcobalamin II deficiency; Agammaglobulinemia; pancytopenia; neutropenic colitis; failure to thrive; Transcobalamin II deficiency; can have a presentation similar to severe combined immunodeficiency; hypotonia, myoclonic like movements, pallor, purpura, anaemia, thrombocytopenia, megaloblastosis, aplastic bone marrow to Transcobalamin II deficiency MIM# 275350; Decreased Ig levels; Megaloblastic anaemia; pancytopaenia; Reticulocytopaenia; failure to thrive; diarrhoea; hypogammaglobulinaemia; pallor; hypotonia; respiratory infection; if untreated (B12) for prolonged periods results in intellectual disability
Set publications
Zornitza Stark (Victorian Clinical Genetics Services; Australian Genomics)Publications for gene: TCN2 were set to 10518276; 7849710
Set Phenotypes, Set publications
Zornitza Stark (Victorian Clinical Genetics Services; Australian Genomics)Added phenotypes megaloblastic bone marrow; thrombocytopenia; 275350 Transcobalamin II deficiency; Agammaglobulinemia; pancytopenia; neutropenic colitis; can have a presentation similar to severe combined immunodeficiency; failure to thrive; Transcobalamin II deficiency; neutropenia; hypotonia, myoclonic like movements, pallor, purpura, anaemia, thrombocytopenia, megaloblastosis, aplastic bone marrow for gene: TCN2 Publications for gene TCN2 were updated from 7849710; 10518276 to 10518276; 7849710
Created, Added New Source, Set mode of inheritance, Set publications, Set Phenotypes
Zornitza Stark (Victorian Clinical Genetics Services; Australian Genomics)gene: TCN2 was added gene: TCN2 was added to Rare anaemia_GEL. Sources: London South GLH,North West GLH,Expert Review Green,Wessex and West Midlands GLH,NHS GMS,Yorkshire and North East GLH Mode of inheritance for gene: TCN2 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: TCN2 were set to 7849710; 10518276 Phenotypes for gene: TCN2 were set to failure to thrive; neutropenia; hypotonia, myoclonic like movements, pallor, purpura, anaemia, thrombocytopenia, megaloblastosis, aplastic bone marrow; Transcobalamin II deficiency; can have a presentation similar to severe combined immunodeficiency; Agammaglobulinemia; neutropenic colitis; thrombocytopenia; 275350 Transcobalamin II deficiency; megaloblastic bone marrow; pancytopenia