Introduction
Results
Mutation | Men | Women | Total |
---|---|---|---|
G551D | 1 | 2 | 3 |
R553X | 0 | 1 | 1 |
F508del | 35 | 32 | 67 |
N1303K | 7 | 8 | 15 |
I148T | 4 | 9 | 13 |
G542X | 3 | 6 | 9 |
DI507 | 2 | 0 | 2 |
L1077P | 0 | 2 | 2 |
D1152H | 1 | 6 | 7 |
W1282X | 2 | 0 | 2 |
2183 AA>G | 3 | 0 | 3 |
1259insA | 0 | 1 | 1 |
4016insT | 1 | 0 | 1 |
I507del | 1 | 0 | 1 |
2789+5G>A | 1 | 0 | 1 |
4382delA | 0 | 2 | 2 |
G1244E | 1 | 0 | 1 |
621+3A>G | 1 | 0 | 1 |
Total | 63 | 69 | 132 |
Discussion
Castaldo et al.[14] | Mutations observed in the present study | |
---|---|---|
F508del
| 55.8% (29) | 48.62% (141) |
N1303K
| 3.8% (2) | 9.31% (27) |
G542X
| 3.8% (2) | 8.96% (26) |
W1282X
| 3.8% (2) | 1.03% (3) |
2183AA>G
| 5.8% (3) | 2.76% (8) |
R1162X
| 0 | 0 |
1717-1G>A
| 1.9% (1) | 0 |
T338I
| 0 | 0 |
R347P
| 0 | 0.69% (2) |
711+5G>A
| 0 | 0 |
852del22
| 5.8% (3) | 1.03% (3) |
4382delA
| 0 | 0.69% (2) |
1259insA
| 0 | 0.34% (1) |
4016insT
| 0 | 0.34% (1) |
R553X
| 0 | 0.34% (1) |
R1158X
| 0 | 0 |
L1077P
| 0 | 1.03% (3) |
I502T
| 0 | 0 |
3849+10kbC>T
| 1.9% (1) | 0.34% (1) |
D579G
| 0 | 0.69% (2) |
G1244E
| 3.8% (2) | 0 |
G1349D
| 0 | 0.34% (1) |
2789+5G>A
| 0 | 1.03% (3) |
711+1G>T
| 0 | 0 |
L1065P
| 0 | 0 |
2522insC
| 0 | 0 |
E585X
| 0 | 0 |
G85E
| 0 | 0 |
G178R
| 0 | 0 |
D1152H
| 0 | 3.10% (9) |
I148T-3195del6
| 0 | 0 |
I148T (alone)
| 0 | 4.48% (13) |
R334W
| 0 | 0 |
DI507
| 0 | 0.69% (2) |
I1005R
| 0 | 0 |
3272-26A>G
| 0 | 0 |
2711delT
| 0 | 0 |
L558S
| 1.9% (1) | 0.34% (1) |
W1063X
| 0 | 0 |
D110H
| 0 | 0 |
S549R (A>C)
| 1.9% (1) | 0.69% (2) |
2184insA
| 0 | 0 |
3131del22
| 0 | 0 |
R709N
| 0 | 0 |
A349V
| 0 | 0 |
4015insA
| 0 | 0 |
Y849X
| 1.9% (1) | 0.34% (1) |
G551D
| 0 | 1.03% (3) |
621+3A>G
| 0 | 0.34% (1) |
E831X
| 0 | 0 |
I507del
| 0 | 0.69% (2) |
IVS8 TG12/t5
| 0 | 1.03% (3) |
H139R (A->G)
| 0 | 0.34% (1) |
1248+1G>A
| 0 | 0.34% (1) |
R74W;V201M;D1270N
| 0 | 0.69% (2) |
S1455X
| 0 | 0.34% (1) |
dele 2,3 (21kb)
| 0 | 0.34% (1) |
991del5
| 0 | 0.34% (1) |
UNKNOWN
| 7 %(4) | 4.83% (14) |
F508C
| 0 | 0.69% (2) |
TOTAL
|
52
|
290
|
Conclusions
Methods
-
DNA isolation, starting from 25μl of blood, using the Promega extraction kit (DNA IQ™ System, cod.C6701; Promega Italy S.r.l., Milan, Italy).
-
Polymerase chain reaction (PCR) and reverse hybridization. The procedure includes two steps: PCR amplification using biotinylated primers and hybridization of amplification products to a test strip containing allele-specific oligonucleotide probes immobilized as an array of parallel lines. Bound biotinylated sequences are detected using streptavidin-alkaline phosphatase and color substrates. The amplification and the reverse hybridization on a strip were obtained with the use of commercial kits produced by Nuclear Laser Medicine S.r.l., Settala (MI), Italy (cod. AC023/AC025 and AC089): genetic tests aimed at checking 60 mutations in the CFTR genes. The mutations analyzed are listed in Table 3. The test has a sensitivity and a specificity of more than 99%. With a direct analysis of 60 mutations of the CTFR gene, with reverse dot blot, it is possible to detect 90% of the most common CF alleles in Southern Italy (the regions of Campania, Puglia, Basilicata and Molise).
-
The patients who tested negative or with a single mutation detected by reverse dot blot and with a clinical suspicion of atypical cystic fibrosis were analyzed with a complete scanning of the codificant region, through amplification and direct sequencing of 27 exones of the CFTR gene. In patients negative for reverse dot blot and in whom there were no clinical signs of cystic fibrosis, sequencing of the CFTR gene was not necessary. DNA sequencing is not essential, since the detection of innocent polymorphisms is not important to control the disease. The sequence of oligonucleotides for each exone, with the annealing temperatures (T°A) and the length in base pair (bp) of the amplified product, are reported in Table 4. The amplification conditions for the 27 exones change according to the annealing temperature (T°A.), which depends on the oligonucleotides used, which in turn are specific for analysis of each exone. The amplification report is shown in Table 5.
F508del | I507del | F508C | 621+1G>T | D110H | E585X | G1349D |
I502T | 1706del17 | 1677delTA | R117H | H139R | 1898+1G>A | 4015delA |
G542X | 1717-1G>A | Q552X | 852del22 | G178R | 1898+3A>G | |
G551D | S549R(A>C) | 2183AA>G | T338I | 991del5 | 1898+5G>T | |
N1303K | 4016insT | 3849+10kb C>T | R347P | R334W | 2184insA | |
G85E | 711+5G>A | 711+1G>T | 1259insA | R347H | 2522insC | |
2789+5G>A | W1282X | G1244E | R1066H | R352Q | 3120+1G>A | |
I148T | 3199del6 | S912X | R1158X | 1717-8G>A | R1066C | |
R1162X | 4382delA | D1152H | L1077P | D579G | 3272-26A>G | |
L1065P | R553X | PoliT: 5T, 7T, 9T | 1874insT | 3659delC |
Exon | Sequence of primers | T°A | bp |
---|---|---|---|
1 | GAGAAAGCCGCTAGAGCAAA(CF1F) | 55°C | 394 |
TCCTTTACCCCAAACCCAAC(CF1R) | |||
2 | TCCAAATCTGTATGGAGACCA(CF2F) | 55°C | 603 |
TCAGTGTGAAAATGAGATGTTCC(CF2R) | |||
3 | TCTGGCTGAGTGTTTGGTGT(CF3F) | 55°C | 399 |
TTTGGAGTTGGATTCATCCTTT(CF3R) | |||
4 | AAACTTGTCTCCCACTGTTGC(CF4F) | 55°C | 453 |
GGCCTGTGCAAGGAAGTATT(CF4R) | |||
5 | GTGCCTAGATGCTGGGAAAT(CF5F) | 55°C | 393 |
AAAACTCCGCCTTTCCAGTT(CF5R) | |||
6a | TGCTATGTGCTCCATGTAATGA(CF6AF) | 55°C | 415 |
TGCATAGAGCAGTCCTGGTT(CF6AR) | |||
6b | TGCCCATCTGTTGAATAAAAG(CF6BF) | 55°C | 411 |
CCCATGAAAGTGAATTTGTGC(CF6BR) | |||
7 | TTCCATTCCAAGATCCCTGA(CF7F) | 55°C | 404 |
GCACATTTTTGCAAAGTTCA(CF7F) | |||
8 | GAATCCTAGTGCTTGGCAAAT(CF8F) | 55°C | 404 |
GATCCTCCTTCCAGTTCTACCA(CF8R) | |||
9 | GGCCATGTGCTTTTCAAACT(CF9F) | 55°C | 389 |
CTCCAAAAATACCTTCCAGCA(CF9R) | |||
10 | TGAATCCTGAGCGTGATTTG(CF10F) | 55°C | 435 |
TTCATGTGTTTGCAAGCTTCTT(CF10R) | |||
11 | GAAGGAAGATGTGCCTTTCAA(CF11F) | 55°C | 395 |
CCAAGATACGGGCACAGATT(CF11R) | |||
12 | TCAGTGAATCGATGTGGTGAC(CF12F) | 55°C | 419 |
ATGAGGCGGTGAGAAAAGGT(CF12R) | |||
13-1 | TCATGCTATCAGAATTCACAAGG(CF13F1) | 56°C | 575 |
GGGAGTCTTTTGCACAATGG(CF13R1) | |||
13-2 | CTGGAGAGTTTGGGGAAAAA(CF13F2) | 56°C | 449 |
AAATACCCCCAAGCGATGTA(CF13R2) | |||
14a | CAATGGTGGCATGAACTGT(CF14AF) | 55°C | 437 |
GTGGTTCTACTTGTTGATTTTTCAG(CF14AR) | |||
14b | TGGCTTTCTTGTGAGGTTCA(CF4BF) | 55°C | 446 |
TGCTTGGGAGAAATGAAACA(CF14BR) | |||
15 | GTCGCCAAATAACGATTTCC(CF15F) | 55°C | 406 |
AGGTTCAACAAAGGGCACAT(CF15R) | |||
16 | TTTGGGTTCTGAATGCGTCT(CF16F) | 55°C | 388 |
GGCCAGGTAAGCAGTTCTGA(CF16R) | |||
17a | CTCACCAACATGTTTTCTTTGA(CF17AF) | 55°C | 399 |
CCAAAATGAAGTCACATGGTCA(CF17AR) | |||
17b | GAATGGCACCAGTGTGAAAA(CF17BF) | 55°C | 682 |
CAATCTGTGTGCATCGGTTT(CF17BR) | |||
18 | TGTGCCCTAGGAGAAGTGTG(CF18F) | 55°C | 335 |
TGACAGATACACAGTGACCCTCA(CF18R) | |||
19 | GCCCGACAAATAACCAAGTG(CF19F) | 55°C | 399 |
GCAAGCAGTGTTCAAATCTCA(CF19R) | |||
20 | CCAATTCCTTATGCCCAGTT(CF20F) | 55°C | 408 |
TGGCTAAGTCCTTTTGCTCA(CF20R) | |||
21 | TGATGGTAAGTACATGGGTGTTTC(CF21F) | 57°C | 578 |
GGAGCCATACCAGTGAGGAG(CF21R) | |||
22 | TCAAATGGTGGCAGGTAGTG(CF22F) | 55°C | 382 |
TCACCATGAAGCAGGCATAA(CF22R) | |||
23 | CCCATGGTTGAAAAGCTGAT(CF23F) | 55°C | 417 |
TGAGTAAAGCTGGATGGCTG(CF23R) | |||
24 | GCCTTCTGTCCCAGATCTCA(CF24F) | 60°C | 362 |
GAGCAAATGTCCCATGTCAA(CF24R) |
Temperature | Time | Cycles |
---|---|---|
95°C | 5’ | 1 |
95°C | 30” | 35 |
T° A | 30” | |
72°C | 20” | |
72°C | 5’ | 1 |