title: Expanding the mutation spectrum in 130 probands with ARPKD: identification of 62 novel PKHD1 mutations by sanger sequencing and MLPA analysis.
abstract: Autosomal recessive polycystic kidney disease (ARPKD) is a rare severe genetic disorder arising in the perinatal period, although a late-onset presentation of the disease has been described. Pulmonary hypoplasia is the major cause of morbidity and mortality in the newborn period. ARPKD is caused by mutations in the PKHD1 (polycystic kidney and hepatic disease 1) gene that is among the largest human genes. To achieve a molecular diagnosis of the disease, a large series of Italian affected subjects were recruited. Exhaustive mutation analysis of PKHD1 gene was carried out by Sanger sequencing and multiple ligation probe amplification (MLPA) technique in 110 individuals. A total of 173 mutations resulting in a detection rate of 78.6% were identified. Additional 20 unrelated patients, in whom it was not possible to analyze the whole coding sequence, have been included in this study. Taking into account the total number (n=130) of this cohort of patients, 107 different types of mutations have been detected in 193 mutated alleles. Out of 107 mutations, 62 were novel: 11 nonsense, 6 frameshift, 7 splice site mutations, 2 in-frame deletions and 2 multiexon deletion detected by MLPA. Thirty-four were missense variants. In conclusion, our report expands the spectrum of PKHD1 mutations and confirms the heterogeneity of this disorder. The population under study represents the largest Italian ARPKD cohort reported to date. The estimated costs and the time invested for molecular screening of genes with large size and allelic heterogeneity such as PKHD1 demand the use of next-generation sequencing (NGS) technologies for a faster and cheaper screening of the affected subjects.
authors.affiliation: Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza Hospital, San Giovanni Rotondo, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Melchionda
authors.affiliation: Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza Hospital, San Giovanni Rotondo, Italy.
authors.forename: Teresa
authors.initials: T
authors.lastname: Palladino
authors.affiliation: Bioinformatics Unit, IRCCS Casa Sollievo della Sofferenza-Mendel, Rome, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Castellana
authors.affiliation: Pediatric Nephrology and Dialysis Unit, Pediatric Hospital Giovanni XXIII, Bari, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Giordano
authors.affiliation: Pediatric Nephrology, Dialysis and Transplant Unit, Women's and Children's Health Department, University of Padua, Padua, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Benetti
authors.affiliation: Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza Hospital, San Giovanni Rotondo, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: De Bonis
authors.affiliation: Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza Hospital, San Giovanni Rotondo, Italy.
authors.forename: Leopoldo
authors.initials: L
authors.lastname: Zelante
authors.affiliation: Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza Hospital, San Giovanni Rotondo, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Bisceglia
mesh_terms: D000293:Adolescent; D000328:Adult; D000483:Alleles; D019943:Amino Acid Substitution; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D005260:Female; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D060885:Multiplex Polymerase Chain Reaction; D009154:Mutation; D017044:Polycystic Kidney, Autosomal Recessive / Q000175:diagnosis / Q000235:genetics*; D011956:Receptors, Cell Surface / Q000235:genetics*; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: C451750:PKHD1 protein, human; D011956:Receptors, Cell Surface