TY - JOUR

T1 - Targeted sequencing reveals complex, phenotype-correlated genotypes in cystic fibrosis

AU - Ivanov, Maxim

AU - Matsvay, Alina

AU - Glazova, Olga

AU - Krasovskiy, Stanislav

AU - Usacheva, Mariya

AU - Amelina, Elena

AU - Chernyak, Aleksandr

AU - Ivanov, Mikhail

AU - Musienko, Sergey

AU - Prodanov, Timofey

AU - Kovalenko, Sergey

AU - Baranova, Ancha

AU - Khafizov, Kamil

PY - 2018/2/13

Y1 - 2018/2/13

N2 - Background: Cystic fibrosis (CF) is one of the most common life-threatening genetic disorders. Around 2000 variants in the CFTR gene have been identified, with some proportion known to be pathogenic and 300 disease-causing mutations have been characterized in detail by CFTR2 database, which complicates its analysis with conventional methods. Methods: We conducted next-generation sequencing (NGS) in a cohort of 89 adult patients negative for p.Phe508del homozygosity. Complete clinical and demographic information were available for 84 patients. Results: By combining MLPA with NGS, we identified disease-causing alleles in all the CF patients. Importantly, in 10% of cases, standard bioinformatics pipelines were inefficient in identifying causative mutations. Class IV-V mutations were observed in 38 (45%) cases, predominantly ones with pancreatic sufficient CF disease; rest of the patients had Class I-III mutations. Diabetes was seen only in patients homozygous for class I-III mutations. We found that 12% of the patients were heterozygous for more than two pathogenic CFTR mutations. Two patients were observed with p.[Arg1070Gln, Ser466] complex allele which was associated with milder pulmonary obstructions (FVC 107 and 109% versus 67%, CI 95%: 63-72%; FEV 90 and 111% versus 47%, CI 95%: 37-48%). For the first time p.[Phe508del, Leu467Phe] complex allele was reported, observed in four patients (5%). Conclusion: NGS can be a more information-gaining technology compared to standard methods. Combined with its equivalent diagnostic performance, it can therefore be implemented in the clinical practice, although careful validation is still required.

AB - Background: Cystic fibrosis (CF) is one of the most common life-threatening genetic disorders. Around 2000 variants in the CFTR gene have been identified, with some proportion known to be pathogenic and 300 disease-causing mutations have been characterized in detail by CFTR2 database, which complicates its analysis with conventional methods. Methods: We conducted next-generation sequencing (NGS) in a cohort of 89 adult patients negative for p.Phe508del homozygosity. Complete clinical and demographic information were available for 84 patients. Results: By combining MLPA with NGS, we identified disease-causing alleles in all the CF patients. Importantly, in 10% of cases, standard bioinformatics pipelines were inefficient in identifying causative mutations. Class IV-V mutations were observed in 38 (45%) cases, predominantly ones with pancreatic sufficient CF disease; rest of the patients had Class I-III mutations. Diabetes was seen only in patients homozygous for class I-III mutations. We found that 12% of the patients were heterozygous for more than two pathogenic CFTR mutations. Two patients were observed with p.[Arg1070Gln, Ser466] complex allele which was associated with milder pulmonary obstructions (FVC 107 and 109% versus 67%, CI 95%: 63-72%; FEV 90 and 111% versus 47%, CI 95%: 37-48%). For the first time p.[Phe508del, Leu467Phe] complex allele was reported, observed in four patients (5%). Conclusion: NGS can be a more information-gaining technology compared to standard methods. Combined with its equivalent diagnostic performance, it can therefore be implemented in the clinical practice, although careful validation is still required.

KW - CFTR cystic fibrosis

KW - NGS next generation sequencing

KW - Cystic Fibrosis Transmembrane Conductance Regulator/deficiency

KW - Genetic Association Studies

KW - Biomarkers/analysis

KW - Humans

KW - Middle Aged

KW - Male

KW - High-Throughput Nucleotide Sequencing/methods

KW - Young Adult

KW - Adult

KW - Female

KW - Mutation

KW - Cystic Fibrosis/genetics

KW - Cohort Studies

KW - POPULATION

KW - VARIANTS

KW - CFTR GENE

KW - MISSENSE MUTATIONS

KW - ORIGIN

KW - SERVER

KW - DISEASE

KW - SPECTRUM

KW - CONDUCTANCE REGULATOR GENE

UR - http://www.scopus.com/inward/record.url?scp=85042057939&partnerID=8YFLogxK

U2 - 10.1186/s12920-018-0328-z

DO - 10.1186/s12920-018-0328-z

M3 - Article

C2 - 29504914

AN - SCOPUS:85042057939

VL - 11

SP - 13

JO - BMC Medical Genomics

JF - BMC Medical Genomics

SN - 1755-8794

IS - Suppl 1

M1 - 13

ER -