Curation FAME4 YEATS2

Gene YEATS2
Disease FAME4
Inheritance AD
Score

3 + 3 = 6 / 18

Genetic + experimental = total
Classification
0
18
Refuted
Moderate
Definitive
Last Updated 08/18/2025
Pubs Reviewed 3
Publication Span 11 years
Publication Interval 11 years
Curator(s) Macayla Weiner, Laurel Hiatt, Elbay Aliyev
Description

Familial adult myoclonic epilepsy type 4 (FAME4) is an autosomal dominant disorder associated with intronic YEATS2 pentanucleotide repeat expansion/insertion. In a Thai BAFME4 family, long-read sequencing identified a YEATS2 intron 1 (TTTTA)n expansion with a TTTCA insertion, and RP-PCR/long-range PCR showed segregation of TTTCA insertions with disease in 13 affected relatives and absence from eight unaffected relatives and 1116 Thai controls. Earlier linkage mapped the disease locus to 3q26.32-q28. Gene-level Drosophila knockdown studies support a neuronal role for YEATS2.

Genetic evidence

Total: 3

Category
Type
Citation
Score
Details
Singular Evidence
Probands
1.5

One Thai BAFME4 family/proband: long-read sequencing identified an intronic YEATS2 (TTTTA)n expansion with TTTCA insertion; RP-PCR and long-range PCR confirmed expanded alleles in affected family members, with TTTCA absent from unaffected relatives and 1116 Thai controls.

Collective Evidence
Segregation
1.5

Genome-wide linkage in a Thai autosomal dominant BAFME family with 13 affected members mapped disease to chromosome 3q26.32-q28; D3S1262 had maximum two-point LOD 5.419 at θ=0, refined to a 10 Mb interval between D3S3730 and D3S1580.

Experimental evidence

Total: 3

Category
Type
Citation
Score
Details
Function
Biochemical function
0.5

Gene-level evidence: pan-neuronal dYEATS2 knockdown in Drosophila reduced dopamine content and lowered tyrosine hydroxylase transcript/protein levels, supporting a role for YEATS2 in dopamine biosynthesis; the human repeat expansion was not directly modeled.

Function
Regulatory impact
0.5

Gene-level expression evidence: dYEATS2 knockdown altered dopaminergic pathway expression markers, including reduced tyrosine hydroxylase and changes in vMAT/D2R; the study did not directly test regulatory effects of the human intronic TTTTA/TTTCA expansion.

Models
Non-human model organism
2

Drosophila pan-neuronal dYEATS2 knockdown caused seizure-like behaviours after electric, thermal, and mechanical stress, with locomotor/social/exploratory deficits; L-DOPA improved seizure-like and exploratory phenotypes. This models YEATS2 loss of function, not the human repeat expansion.

Maximum score caps apply at evidence type, category, and supercategory levels, so section totals may be lower than the raw sum of row scores.