Table 1.

Types and number of variations within the interferon-γ (IFN-γ) gene

Type of variation	Description	Number present in IFN-γ gene
Splice donor variant	A splice variant that changes the two-base region at the 5′ end of an intron	1
Gain of stop variant	A sequence variant whereby a premature stop codon is created, leading to a shortened transcript	1
Loss of stop variant	A sequence variant whereby at least one base of the stop codon is changed, resulting in an elongated transcript	1
Non-synonymous (Missense) variant	A sequence variant, that changes one or more bases, resulting in a different amino acid sequence but where the transcript length is preserved	31
Splice region variant	A sequence variant in which a change has occurred within the region of the splice site, either within one or three bases of the exon or three to eight bases of the intron	7
Synonymous variant	A sequence variant where there is no resulting change to the encoded amino acid or transcript length	10
5′ UTR variant	A variant in the 5′ untranslated region (UTR). This is upstream of the gene	3
3′ UTR variant	A variant in the 3′ untranslated region (UTR). This is downstream of the gene	16
Intron variant	A variant that occurs within an intron	119
Upstream gene variant	A sequence variant located 5′ (upstream) of a gene	119
Downstream gene variant	A sequence variant located 3′ (downstream) of a gene	118

A codon is a group of three bases that code for one amino acid, or start/stop signal. Data from Ensembl website¹⁴.