Table 1. Mutational spectrum of CHM characterized families.
| Mutation | Effect | Methods | Origin | Described/Novela | n | Relative frequency (%)b |
|---|---|---|---|---|---|---|
| Translocation | ||||||
| 46,X,t (X;4)(q21:p16) | de novo translocation X;4 [t X;4] | Karyotype+FISH | Spain | Described in our cohort[7] | 1 | 3 |
| Genomic deletion | ||||||
| c.-29-*3450del1931185 | Complete CHM and DACH2 deletion | qF-PCR+aCGH | Spain | This study | 1 | 3 |
| c.-29-*3450del1514526 | Complete CHM and DACH2 deletion | qF-PCR+aCGH | Spain | Described in our cohort[6] | 1 | 3 |
| c.-29-*3450del445660 | Complete CHM deletion | qF-PCR+aCGH | Spain | This study | 1 | 3 |
| c.-29-?_49+?del(no longer 24.4Kb) | Promoter to intron 1 deletion | Direct sequencing+ aCGH | Spain | Firstly demarcated in this study | 1 | 3 |
| c.-29-?_116+?del | Promoter to exon 2 deletion | Direct sequencing+ aCGH | Spain | Described | 1 | 3 |
| c.50-116del1992 | Exon 2 deletion | RNA studies+aCGH | Spain | Firstly demarcated in this study | 1 | 3 |
| c.189+34_*3450+?del | Exon 4 to exon 15 deletion | qF-PCR+MLPA | Spain | Firstly demarcated in this study | 1 | 3 |
| c.117-314del48634 | Exon 3 and exon 4 deletion | RNA studies+aCGH | Spain | Firstly demarcated in this study | 1 | 3 |
| c.703-?_940+? | Exon 6 and exon 7 deletion | qF-PCR | Unknown | Described | 1 | 3 |
| c.1167-1244del11149 | Exon 9 deletion | qF-PCR+MLPA | Portugal | Firstly demarcated in this study | 1 | 3 |
| c.1167-?_1244+?del | Exon 9 deletion | qF-PCR+MLPA | Spain | Described | 3 | 9 |
| Splicing | ||||||
| c.189+1G>A | Exon 3 skipping | Direct sequencing/NGS panel | Spain | Described | 2 | 6 |
| c.1167-1G>T | Exon 9 skipping | NGS panel | Spain | This study | 1 | 3 |
| c.1167-2A>G | Exon 9 skipping | Direct sequencing | Spain | This study | 1 | 3 |
| Frameshift | ||||||
| c.641_642delGA | p.Arg214Asnfs*8 | Direct sequencing | Spain | Described in our cohort[6] | 1 | 3 |
| c.525_526delAG | p.Lys178Argfs*5 | Direct sequencing | 1 Portugal; 1 Spain | Described | 2 | 6 |
| c.862dupA | p.Thr288Asnfs*19 | WES | Spain | Described in our cohort[6] | 1 | 3 |
| Nonsense | ||||||
| c.116C>A | p.Ser39* | Direct sequencing | Spain | Described | 1 | 3 |
| c.141G>A | p.Trp47* | Direct sequencing | Spain | Described | 2 | 6 |
| c.256C>T | p.Gln76* | Direct sequencing | Spain | Described | 1 | 3 |
| c.339T>G | p.Tyr103* | Direct sequencing | Spain | Described | 1 | 3 |
| c.745C>T | p.Arg239* | Direct sequencing | Spain | Described | 1 | 3 |
| c.877C>T | p.Arg293* | Direct sequencing | 1 Portugal; 1 Poland;2 Spain | Described | 4 | 12 |
| c.1048C>A | p.Ser340* | Direct sequencing | Spain | Described in our cohort [10] | 1 | 3 |
| c.1272_1273invTC | p.Gln425* | Direct sequencing | Spain | This study | 1 | 3 |
| c.1471G>T | p.Glu491* | Direct sequencing | Spain | Described | 1 | 3 |
| c.1703T>A | p.Leu568* | Direct sequencing | Spain | This study | 1 | 3 |
| Missense | ||||||
| c.49G>T | p.Gly17Cys | Direct sequencing | Belgium | This study | 1 | 3 |
a Present on Human Gene Mutation Database (HGMD) or Locus specific database (LSDB).
b Calculated relative to 36 CHM families characterized in the laboratory.