Table 1.
List of Irish MMR mutations recorded in carriers
| Gene | MMR mutation | Clinical significance | Location | No. of families with mutation | Total no. of confirmed carriers |
|---|---|---|---|---|---|
| MLH1 | c.1731 + 1G > A | Pathogenic | NR | 1 | 5 |
| MLH1 | c.1928_1931dupTTGA (p.Asn645) | Pathogenic | NR | 1 | 5 |
| MLH1 | c.544A > G (p.Arg182Gly) | Pathogenic | Exon 6 | 1 | 11 |
| MLH1 | c.350C > T (pThr117Met) | Pathogenic | Exon 4 | 2 | 6 |
| MLH1 | c.1664 T > C (p.Leu555Pro) | Pathogenic | Exon 14 | 1 | 1 |
| MLH1 | c.589-9_589-6delGTTT | Variant of unknown significance (2013 InSiGHT) | Intron 7 | 1 | 1 |
| MLH1 | c.735delC (p.Tyr245) | Pathogenic | Exon 9 | 1 | 1 |
| MLH1 | c.94delA | Pathogenic | Exon 1 | 1 | 2 |
| MLH1 | C.84_86dupAGC p. (Ala29dup) | Pathogenic | Exon 1 | 1 | 1 |
| MLH1 | c.84_86dupAGC (p.Ala29dup) | Pathogenic | Exon 1 | 1 | 1 |
| MLH1 | IVS15 + 1G > A | Pathogenic | NR | 1 | 3 |
| MLH1 | deletion | Pathogenic | exons 3–6 | 1 | 1 |
| MLH1 | c.1937A > G (p.Tyr646Cys) | Pathogenic | exon 17 | 1 | 1 |
| MLH1 | deletion | Pathogenic | exon 6–8 | 1 | 1 |
| MLH1 | c.1990-1G > C | Pathogenic | exon 18 | 2 | 3 |
| MLH1 | IVS17 + 5 > A | Pathogenic | NR | 1 | 1 |
| MLH1 | c.1943C > T (p.Pro648Leu) | Pathogenic | exon 17 | 1 | 2 |
| MLH1 | 366-69delAAAG | Pathogenic | exon 4 | 1 | 5 |
| MLH1 | Hypermethylation | Pathogenic | MLH1 promoter region | 1 | 1 |
| MLH1 | Constitutional epimutation | Pathogenic | MLH1 promoter region | 1 | 1 |
| MSH2 | c.1684G > T (p.Glu562X) | Pathogenic | NR | 1 | 4 |
| MSH2 | c.1786_1788delAA (p.Asn596del) | Pathogenic | exon 12 | 1 | 1 |
| MSH2 | IVS5 + 3A > T deletion | Pathogenic | NR | 2 | 2 |
| MSH2 | c.2251G > A (p.Gly751Arg) | Pathogenic | exon 14 | 2 | 4 |
| MSH2 | p.A305T:GCA > ACA | Variant of uncertain significance (InSiGHT 2018) | NR | 1 | 1 |
| MSH2 | c.2131_2133delCGA (p.Arg71del) | NR | NR | 1 | 1 |
| MSH2 | CAT>TAT codon 639 His>Tyr | Pathogenic | NR | 1 | 3 |
| MSH2 | 2370insT | Pathogenic | exon 14 | 1 | 4 |
| MSH2 | L277X deletion | Pathogenic | NR | 1 | 1 |
| MSH2 | c.3261delC (p. Phe1088Serfs”2) | Pathogenic | NR | 1 | 1 |
| MSH2 | c.1277-1G > C | Pathogenic | exon 8 | 1 | 1 |
| MSH2 | c.1738_1741delGAAA (p.Glu580Leufs*9) | Pathogenic | exon 11 | 1 | 1 |
| MSH2 | intron 12 rearrangement | Pathogenic | intron 12 | 1 | 1 |
| MSH2 | c.212-1G > A | Pathogenic | NR | 1 | 1 |
| MSH2 | heterozygous deletion | Pathogenic | exon 1–8 | 2 | 3 |
| MSH2 | c.2050delG (p.Val684) | Pathogenic | NR | 1 | 1 |
| MSH2 | c.942 + 3A > T | Pathogenic | intron 5 | 1 | 1 |
| MSH2 | deletion S743X | Pathogenic | NR | 1 | 1 |
| MSH2 | c.342 + 3A > T | Pathogenic | exon 5 | 1 | 4 |
| PMS2 | c.137G > T (p.Ser46Ile) | Pathogenic | exon 2 | 4 | 14 |
| PMS2 | deletion | Pathogenic | exon 9–15 | 1 | 1 |
| PMS2 | deletion | Pathogenic | exons 6–8 | 1 | 1 |
| PMS2 | deletion | Pathogenic | exons 1–15 | 1 | 1 |
| MSH6 | deletion | Pathogenic | exons 1–6 | 1 | 3 |
| MSH6 | c.770dupA(p.Asp257GlufsX6) | Pathogenic | exon 4 | 1 | 1 |
| MSH6 | 3702-3702insAGAA | Pathogenic | NR | 1 | 1 |
| MSH6 | c.334C > T (p.Gln132X) | Pathogenic | exon 2 | 1 | 1 |
| MSH6 | c.2061 T > A (p.Cys687X) | Pathogenic | exon 4 | 1 | 2 |
| MSH6 | c.2974G > T (p.(GLU992”)) | Pathogenic | NR | 1 | 2 |
| MSH6 | c.341dupG p. (Lys114GInfs”240) | Pathogenic | NR | 1 | 1 |
| EPCAM | EX6_3’UTRdel | Pathogenic | NR | 1 | 2 |
NR not recorded