Polymorphisms in base excision repair genes: Breast cancer risk and individual radiosensitivity

Table 1 List of meta-analyses on X-ray repair cross-complementing group 1 single nucleotide polymorphisms and haplotypes and risk of breast cancer

Ref.	XRCC1 SNPs	Number of studies analysed	Result
Huang et al[17]	Arg399Gln	37	The 399Gln variant allele is associated with an increased risk of BC
	Arg194Trp	18
	Arg280His	8
Li et al[18]	Arg399Gln	40	The recessive effect of the 399Gln variant allele increases the risk of BC (significant only in Asians)
	Arg194Trp	21
	Arg280His	9
Wu et al[19]	Arg399Gln	44	This SNP is associated with increased BC risk in Asians and Africans
Saadat et al[20]	Arg399Gln	36	This SNP is associated with increased BC risk in Asians
Yi et al[13]	Arg399Gln	54	This SNP is associated with increased risk of BC in Asians and Indians
	XRCC1 haplotypes
Saadat[21]	Arg399Gln	10	The Arg194-Gln399 haplotype is associated with increased BC risk in Asians
	Arg194Trp

XRCC1: X-ray repair cross-complementing group 1; SNP: Single nucleotide polymorphism; BC: Breast cancer; Arg: Arginine; Gln: Glutamine; His: Histidine; Trp: Tryptophan.