Table 1.
Standard and Colloquial Nomenclature for CFTR Mutations and Variants
| DNA sequence change* | Amino acid change (three-letter code) | Commonly used colloquial nomenclature | Site of mutation (exon/intron number)§ | Type of mutation |
|---|---|---|---|---|
| c.254G>A | p.Gly85Glu | G85E | Exon 3 | Missense |
| c.350G>A | p.Arg117His | R117H | Exon 4 | Missense |
| c.443T>C† | p.Ile148Thr | I148T | Exon 4 | Missense |
| c.489+1G>T (AJ574942.1:g.240G>T) | 621+1G>T | Intron 4 | Splice site | |
| c.579+1G>T (AJ574943.1:g.261G>T) | 711+1G>T | Intron 5 | Splice site | |
| c.948delT† | p.Phe316LeufsX12 | 1078delT | Exon 7 (no. 8) | Frameshift |
| c.1000C>T | p.Arg334Trp | R334W | Exon 7 (no. 8) | Missense |
| c.1040G>C | p.Arg347Pro | R347P | Exon 7 (no. 8) | Missense |
| c.1210−12T(5_9) (AJ574948.1:g.152T (5_9)) | 5T/7T/9T polymorphism | Intron 8 (no. 9) | Splice site | |
| c.1210−12[5]‡ (AJ574948.1:g.152T[5]‡) | 5T | |||
| c.1210−12T[9]‡ (AJ574948.1:g.152T[9]‡) | 9T | |||
| c.1364C>A | p.Ala455Glu | A455E | Exon 9 (no. 10) | Missense |
| c.1519_1521delATC | p.Ile507del | Delta I507 | Exon 10 (no. 11) | In-frame deletion |
| c.1521_1523delCTT | p.Phe508del | Delta F508 | Exon 10 (no. 11) | In-frame deletion |
| c.1585−1G>A (AJ574980.1:g.116G>A) | 1717−1G>A | Intron 10 (no. 11) | Splice site | |
| c.1624G>T | p.Gly542X | G542X | Exon 11 (no. 12) | Nonsense |
| c.1652G>A | p.Gly551Asp | G551D | Exon 11 (no. 12) | Missense |
| c.1657C>T | p.Arg553X | R553X | Exon 11 (no. 12) | Nonsense |
| c.1679G>C | p.Arg560Thr | R560T | Exon 11 (no. 12) | Missense |
| c.1766+1G>A (AJ574983.1:g.179G>A) | 1898+1G>A | Intron 12 (no. 13) | Splice site | |
| c.2052delA | p.Lys684AsnfsX38 | 2184delA | Exon 13 (no. 14) | Frameshift |
| c.2657+5G>A (AJ574995.1:g.216G>A) | 2789+5G>A | Intron 14b (no. 16) | Splice site | |
| c.2988+1G>T (AJ575003.1:g.305G>T) | 3120+1G>T | Intron 16 (no. 18) | Splice site | |
| c.3437delC | p.Ala1146ValfsX2 | 3569delC | Exon 18 (no. 21) | Frameshift |
| c.3484C>T | p.Arg1162X | R1162X | Exon 19 (no. 22) | Nonsense |
| c.3718−2477C>T (AY848832.1:g.40725C>T) | 3849+10kbC>T | Intron 19 (no. 22) | Other | |
| c.3846G>A | p.Trp1282X | W1282X | Exon 20 (no. 23) | Nonsense |
| c.3909C>G | p.Asn1303Lys | N1303K | Exon 21 (no. 24) | Missense |
If not specified, nucleotide numbering is based on DNA reference sequence NM_000492.3. Note that the version number of this reference sequence may be frequently updated.
These two mutations in the initial 25-mutation panel have been excluded in the recent American College of Medical Genetics recommendations.19
Common repeat polymorphisms should be described as the first nucleotide number, followed by a repeated nucleotide(s), and the number of repeats in square brackets.
Conventional CFTR exon/intron numbering includes exons 6a and 6b, exons 14a and 14b, and exons 17a and 17b; for exon/intron numbers in parentheses, these exon pairs are simply numbered sequentially, without modifiers such as ′6a′ and ′6b.′