Constitutional mismatch repair deficiency…

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Constitutional mismatch repair deficiency syndrome

ORPHA:252202Disease

Also called CMMR-D syndrome

What it is

Constitutional mismatch repair deficiency syndrome is a rare, inherited cancer-predisposing syndrome characterized by the development of a broad spectrum of malignancies during childhood, including mainly brain, hematological and gastrointestinal cancers, although embryonic and other tumors have also been occasionally reported. Non-neoplastic features, in particular manifestations reminiscent of neurofibromatosis type 1 (e.g., café-au-lait spots, freckling, neurofibromas), as well as premalignant and non-malignant lesions (such as adenomas/polpyps) are frequently present before malignancy development.

Key facts

Prevalence
<1 / 1 000 000
Age of onset
Childhood
Inheritance
Autosomal recessive
Classified as
Disease

Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.

Genes

MLH1Disease-causing germline mutation(s)
MSH2Disease-causing germline mutation(s)
MSH6Disease-causing germline mutation(s)
PMS2Disease-causing germline mutation(s)

ICD-10 codes

D80.8filed under a broader ICD-10 category — shared with 6 other rare diseases

ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.

Related health topics

Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.

Cross-references

MONDO 31219OMIM 276300OMIM 619096OMIM 619097OMIM 619101UMLS C4321324

Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.

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