TY - JOUR
T1 - Novel POLG mutations and variable clinical phenotypes in 13 Italian patients
AU - Da Pozzo, Paola
AU - Cardaioli, Elena
AU - Rubegni, Anna
AU - Gallus, Gian Nicola
AU - Malandrini, Alessandro
AU - Rufa, Alessandra
AU - Battisti, Carla
AU - Carluccio, Maria Alessandra
AU - Rocchi, Raffaele
AU - Giannini, Fabio
AU - Bianchi, Amedeo
AU - Mancuso, Michelangelo
AU - Siciliano, Gabriele
AU - Dotti, Maria Teresa
AU - Federico, Antonio
PY - 2016/10/7
Y1 - 2016/10/7
N2 - POLG gene encodes the catalytic subunit of DNA polymerase gamma, essential for mitochondrial DNA (mtDNA) replication and repair. Mutations in POLG have been linked to a spectrum of clinical phenotypes, resulting in autosomal recessive or dominant mitochondrial diseases. These mutations have been associated with heterogeneous phenotypes, presenting with varying severity and at different ages of onset, ranging from the neonatal period to late adult life. We screened 13 patients for POLG mutations. All patients underwent a complete neurological examination, and in most of cases, muscle biopsy was performed. We detected 15 different variations in 13 unrelated Italian patients. Two mutations were novel and mapped in the pol domain (p.Thr989dup and p.Ala847Thr) of the enzyme. We also report new cases carrying controversial variations previously described as incompletely penetrant or a variant of unknown significance. Our study increases the range of clinical presentations associated with mutations in POLG gene, underlining some peculiar clinical features, such as PEO associated with corneal edema, and epilepsy, severe neuropathy with achalasia. The addition of two new substitutions, including the second report of an in-frame duplication, to the growing list of defects increases the value of POLG genetic diagnosis in a range of neurological presentations.
AB - POLG gene encodes the catalytic subunit of DNA polymerase gamma, essential for mitochondrial DNA (mtDNA) replication and repair. Mutations in POLG have been linked to a spectrum of clinical phenotypes, resulting in autosomal recessive or dominant mitochondrial diseases. These mutations have been associated with heterogeneous phenotypes, presenting with varying severity and at different ages of onset, ranging from the neonatal period to late adult life. We screened 13 patients for POLG mutations. All patients underwent a complete neurological examination, and in most of cases, muscle biopsy was performed. We detected 15 different variations in 13 unrelated Italian patients. Two mutations were novel and mapped in the pol domain (p.Thr989dup and p.Ala847Thr) of the enzyme. We also report new cases carrying controversial variations previously described as incompletely penetrant or a variant of unknown significance. Our study increases the range of clinical presentations associated with mutations in POLG gene, underlining some peculiar clinical features, such as PEO associated with corneal edema, and epilepsy, severe neuropathy with achalasia. The addition of two new substitutions, including the second report of an in-frame duplication, to the growing list of defects increases the value of POLG genetic diagnosis in a range of neurological presentations.
KW - Journal Article
U2 - 10.1007/s10072-016-2734-3
DO - 10.1007/s10072-016-2734-3
M3 - Article
C2 - 28130605
JO - Neurological Sciences
JF - Neurological Sciences
SN - 1590-1874
ER -