Variant
RET K666N
NM_020975.6(RET):c.1998G>T (p.Lys666Asn)
- p.Lys666Asn
- p.K666N
- rs146646971
- ClinVar classification
- Pathogenic
- Review status
- 2 stars out of 4criteria provided, multiple submitters, no conflicts
- Last evaluated
- 16 April 2024
Data current to ClinVar release 2026-10-12 · Dante Labs data release 2026.10.16-c6eea6bfFacts last changed 16 October 2026
This page as data
Add .json to the page's address, or ask for application/json, to read it as JSON.
library(jsonlite)
url <- "https://dantelabs.com/genes/ret/variants/k666n.json"
page <- fromJSON(url)
page$variant$nameSummary
K666N is a missense variant in RET: it changes a single amino acid in the protein the gene encodes. ClinVar classifies it as pathogenic or likely pathogenic for Familial Medullary Thyroid Carcinoma (criteria provided, multiple submitters, no conflicts). ClinVar also lists it under 4 more conditions.
ClinVar classifications
| Condition | Classification | Review status | Submissions | Last evaluated |
|---|---|---|---|---|
| Familial Medullary Thyroid CarcinomaClinVar VCV000024932 (opens in a new tab) | Pathogenic/likely pathogenic | 2 stars out of 4criteria provided, multiple submitters, no conflicts | 3 submissions | 16 April 2024 |
| Hereditary pheochromocytomaClinVar VCV000024932 (opens in a new tab) | Pathogenic/likely pathogenic | 2 stars out of 4criteria provided, multiple submitters, no conflicts | 2 submissions | 16 April 2024 |
| Hirschsprung disease, susceptibility to, 1ClinVar VCV000024932 (opens in a new tab) | Pathogenic | 2 stars out of 4criteria provided, multiple submitters, no conflicts | 2 submissions | 16 April 2024 |
| Multiple Endocrine Neoplasia Type 2ClinVar VCV000024932 (opens in a new tab) | Pathogenic/likely pathogenic | 2 stars out of 4criteria provided, multiple submitters, no conflicts | 6 submissions | 16 January 2026 |
| Multiple Endocrine Neoplasia Type 2aClinVar VCV000024932 (opens in a new tab) | Pathogenic/likely pathogenic | 2 stars out of 4criteria provided, multiple submitters, no conflicts | 4 submissions | 16 April 2024 |
Classifications as ClinVar records them in release 2026-10-12. ClinVar updates them as evidence is reviewed.
Where it lies in RET
K666N lies in exon 11 of the 20 in RET's MANE Select transcript, NM_020975.6.
Molecular details
| Gene | RET |
|---|---|
| Transcript | NM_020975.6MANE Select |
| Coding DNA change (HGVS c.) | c.1998G>T |
| Protein change (HGVS p.) | p.Lys666Asnp.K666N |
| Predicted consequence | Missensemissense_variant (opens in a new tab) |
| Predicted impact | Moderate |
| Position (GRCh38) | chr10:43114598 G>T |
| Position (GRCh37) | chr10:43610046 G>T |
| dbSNP ID | rs146646971 (opens in a new tab) |
| ClinVar Variation ID | VCV000024932 (opens in a new tab) |
| ClinVar Allele ID | 36273 |
| ClinGen Allele Registry ID | CA008525 (opens in a new tab) |
| ClinVar name | NM_020975.6(RET):c.1998G>T (p.Lys666Asn) |
RET K666N in other databases
Reports that look at this variant (4)
These Genome Test condition reports include K666N among the variants they look at.
| Report | Conditions | Inheritance |
|---|---|---|
| Hereditary Pheochromocytoma and Paraganglioma | Hereditary pheochromocytoma | Autosomal dominant |
| Hirschsprung Disease & Related Enteric Neurocristopathies | Hirschsprung disease, genetic susceptibility | Autosomal dominant |
| Malignant Endocrine Neoplasm | Malignant Endocrine Neoplasm | |
| Multiple Endocrine Neoplasia | Autosomal dominant | |
| Thyroid Cancer | Thyroid Tumor | |
| Thyroid Cancer | ||
| Thyroid Gland Carcinoma | ||
| Thyroid Gland Adenocarcinoma | ||
| Multiple Endocrine Neoplasia Type 2 | Autosomal dominant | |
| Differentiated Thyroid Carcinoma | ||
| Thyroid Gland Follicular Carcinoma | ||
| Familial Medullary Thyroid Carcinoma | Autosomal dominant | |
| Multiple Endocrine Neoplasia Type 2a | Autosomal dominant | |
| Medullary Thyroid Gland Carcinoma | ||
| Thyroid Gland Disorder |
Other variants in RET
- c.1852T>APathogenic2 stars out of 4
- c.1858T>APathogenic/likely pathogenic2 stars out of 4
- c.1947G>APathogenic/likely pathogenic2 stars out of 4
- c.1998G>CPathogenic/likely pathogenic2 stars out of 4
- c.2370G>TPathogenic2 stars out of 4
- c.2410G>CPathogenic/likely pathogenic2 stars out of 4
- C609RPathogenic2 stars out of 4
- C609YPathogenic2 stars out of 4
- C611FPathogenic2 stars out of 4
- C611YPathogenic2 stars out of 4
Limitations
This page describes publicly available information about a genetic variant. It is not a diagnosis, and it says nothing about whether you or anyone else carries this variant.
Classifications come from ClinVar and change as new evidence is reviewed. A classification here may differ from the one in ClinVar today, or from the one a laboratory reports.
Whole genome sequencing with short reads can miss or miscall some variants, particularly in repeated or highly similar stretches of DNA and in large insertions, deletions or rearrangements.
If you have questions about a variant in your own results or in your family, talk to a genetic counsellor or your doctor.
Sources & credits
- Classifications from ClinVar (release 2026-10-12), National Center for Biotechnology Information.
- Condition terms from the Mondo Disease Ontology (release 2026-10-06), used under CC BY 4.0.
- Gene symbols and names from the HUGO Gene Nomenclature Committee (release 2026-10-16).
- Allele identifiers from the ClinGen Allele Registry (release 2026-10-16-c4908f54).
- Reference SNP identifiers from dbSNP (release b157), National Center for Biotechnology Information.
- Gene–disease links from the Gene Curation Coalition, GenCC (release 2026-10-16).
- Difficult regions from the Genome in a Bottle Consortium (release v3.6).
- Transcripts from MANE (release v1.5), NCBI and EMBL-EBI.
- Predicted consequences from mehari (release 0.11.0), with transcript models from cdot.
- Built from Dante Labs data release 2026.10.16-c6eea6bf of 16 October 2026.
Cite this page
Dante Labs. (16 October 2026). RET K666N (c.1998G>T, rs146646971) (Version 2026.10.16-c6eea6bf). Retrieved 17 October 2026, from https://dantelabs.com/genes/ret/variants/k666n
Dante Labs. RET K666N (c.1998G>T, rs146646971) [Internet]. Version 2026.10.16-c6eea6bf. 16 October 2026 [cited 17 October 2026]. Available from: https://dantelabs.com/genes/ret/variants/k666n
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