Polymorphisms in the IFNL3/IL28B gene and hepatitis C: From adults to children

Table 1 Selected studies exploring the association between single nucleotide polymorphisms in the interferon L3 gene and spontaneous and treatment-induced clearance of hepatitis C virus in adults

Ref.	Number of patients enrolled	SNPs evaluated	Summary of the results
Ge et al[1]	1671	rs12979860	The CC genotype was associated with response to treatment with Peg-IFN-α and ribavirin independent of the ethnicity of the patient
			CC vs CT and TT, OR = 7.3; 95%CI: 5.1-10.4; P = 1.06 × 10-25
Thomas et al[2]	1008	rs12979860	The C allele and CC genotype were associated with spontaneous resolution of HCV infection among individuals of both European and African ancestry
			CT vs CC, OR = 0.35; 95%CI: 0.25-0.48; P = 4 × 10-11; TT vs CC, OR = 0.29; 95%CI: 0.18-0.47; P = 4 × 10-7
Tanaka et al[17]	314	rs12980275 rs8099917	The T allele of the rs8099917 SNP and the A allele of the rs12980275 SNP were associated with response to treatment with Peg-IFN-α and ribavirin Japanese patients
			null virological response vs SVR for rs12980275, OR = 26.7; 95%CI: 9.3-76.5; P = 7.41 × 10-13 and for rs8099917 OR = 36.5; 95%CI: 11.6-114.6; P = 5 × 10-14
Suppiah et al[18]	293	rs8099917	The T allele was associated with response to treatment with Peg-IFN-α and ribavirin in Australian patients
			OR = 1.98; 95%CI: 1.57-2.52; P = 9.25 × 10-9

SNPs: Single nucleotide polymorphisms; HCV: Hepatitis C virus; IFN: Interferon.

Table 2 Paediatric studies exploring the association between single nucleotide polymorphisms in the interferon L3 gene and treatment-induced clearance of hepatitis C virus

Ref.	Number of children enrolled	SNPs evaluated	Summary of the results
Hierro et al[39]	69	rs12979860 rs8099917	The CC genotype of rs12979860 and the T/T genotype of rs8099917 were associated with treatment-induced (IFN monotherapy and Peg-IFN-α and ribavirin association) clearance of HCV (viral genotype data not provided)
Domagalski et al[40]	82	rs12979860rs8099917rs12980275	The CC genotype of rs12979860 and the T/T genotype of rs8099917 were associated with treatment-induced (Peg-IFN-α and ribavirin association) clearance of HCV (viral genotypes 1 and 4; OR = 6.81; 95%CI: 1.98-23.42; P = 0.001 and OR = 3.14; 95%CI: 1.26-7.85; P = 0.013, respectively)
			The rs12980275 SNP was not associated with virological response.
Komatsu et al[41]	63	rs8099917	The rs8099917 SNP was not associated with treatment-induced (response-guided IFN monotherapy and/or Peg-IFN-α and ribavirin association) clearance of HCV (viral genotypes 1, 2, 3 and 4)
Shaker et al[42]	34	rs12979860	The CC genotype of rs12979860 was associated with treatment-induced (Peg-IFN-α and ribavirin association) clearance of HCV (viral genotype 4)
			OR = 2.45; 95%CI not reported; P = 0.02

SNPs: Single nucleotide polymorphisms; HCV: Hepatitis C virus; IFN: Interferon.