Table 1.

Disease-modifying DNA repair genes

Gene	Associated diseases	Principle DNA repair function	Effect on somatic instability	Reference
FAN1	HD, SCAs	ICL repair	Yes	[17–20]
RRM2B	HD, SCA6	Nucleotide salvaging	Unknown	[17, 19–21]
MLH1	HD	MMR	Yes	[17, 19, 21]
MSH3	HD, DM1	MMR	Yes	[18, 19, 22]
PMS2	HD, SCAs	MMR	Yes	[19, 20]
PMS1	HD	MMR	Yes	[19]
LIG1	HD	BER, MMR	Yes	[19]
HTT	HD	BER (at the protein level)	Yes (at the DNA level)	[19, 23]