@article {10768, title = {Cx26 partial loss causes accelerated presbycusis by redox imbalance and dysregulation of Nfr2 pathway.}, journal = {Redox Biol}, volume = {19}, year = {2018}, month = {2018 10}, pages = {301-317}, abstract = {

Mutations in GJB2, the gene that encodes connexin 26 (Cx26), are the most common cause of sensorineural hearing impairment. The truncating variant 35delG, which determines a complete loss of Cx26 protein function, is the prevalent GJB2 mutation in several populations. Here, we generated and analyzed Gjb2 mice as a model of heterozygous human carriers of 35delG. Compared to control mice, auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs) worsened over time more rapidly in Gjb2 mice, indicating they were affected by accelerated age-related hearing loss (ARHL), or presbycusis. We linked causally the auditory phenotype of Gjb2 mice to apoptosis and oxidative damage in the cochlear duct, reduced release of glutathione from connexin hemichannels, decreased nutrient delivery to the sensory epithelium via cochlear gap junctions and deregulated expression of genes that are under transcriptional control of the nuclear factor erythroid 2-related factor 2 (Nrf2), a pivotal regulator of tolerance to redox stress. Moreover, a statistically significant genome-wide association with two genes (PRKCE and TGFB1) related to the Nrf2 pathway (p-value < 4 {\texttimes} 10) was detected in a very large cohort of 4091 individuals, originating from Europe, Caucasus and Central Asia, with hearing phenotype (including 1076 presbycusis patients and 1290 healthy matched controls). We conclude that (i) elements of the Nrf2 pathway are essential for hearing maintenance and (ii) their dysfunction may play an important role in the etiopathogenesis of human presbycusis.

}, keywords = {Animals, Apoptosis, Connexin 26, Female, Gene Deletion, Male, Mice, Mice, Inbred C57BL, NF-E2-Related Factor 2, Oxidation-Reduction, Presbycusis, Signal Transduction}, issn = {2213-2317}, doi = {10.1016/j.redox.2018.08.002}, author = {Fetoni, Anna Rita and Zorzi, Veronica and Paciello, Fabiola and Ziraldo, Gaia and Peres, Chiara and Raspa, Marcello and Scavizzi, Ferdinando and Salvatore, Anna Maria and Crispino, Giulia and Tognola, Gabriella and Gentile, Giulia and Spampinato, Antonio Gianmaria and Cuccaro, Denis and Guarnaccia, Maria and Morello, Giovanna and Van Camp, Guy and Fransen, Erik and Brumat, Marco and Girotto, Giorgia and Paludetti, Gaetano and Gasparini, Paolo and Cavallaro, Sebastiano and Mammano, Fabio} } @article {10568, title = {Common variants in CLDN14 are associated with differential excretion of magnesium over calcium in urine.}, journal = {Pflugers Arch}, volume = {469}, year = {2017}, month = {2017 01}, pages = {91-103}, abstract = {

The nature and importance of genetic factors regulating the differential handling of Ca and Mg by the renal tubule in the general population are poorly defined. We conducted a genome-wide meta-analysis of urinary magnesium-to-calcium ratio to identify associated common genetic variants. We included 9320 adults of European descent from four genetic isolates and three urban cohorts. Urinary magnesium and calcium concentrations were measured centrally in spot urine, and each study conducted linear regression analysis of urinary magnesium-to-calcium ratio on ~2.5 million single-nucleotide polymorphisms (SNPs) using an additive model. We investigated, in mouse, the renal expression profile of the top candidate gene and its variation upon changes in dietary magnesium. The genome-wide analysis evidenced a top locus (rs172639, p~=~1.7~{\texttimes}~10), encompassing CLDN14, the gene coding for claudin-14, that was genome-wide significant when using urinary magnesium-to-calcium ratio, but not either one taken separately. In mouse, claudin-14 is expressed in the distal nephron segments specifically handling magnesium, and its expression is regulated by chronic changes in dietary magnesium content. A genome-wide approach identified common variants in the CLDN14 gene exerting a robust influence on the differential excretion of Mg over Ca in urine. These data highlight the power of urinary electrolyte ratios to unravel genetic determinants of renal tubular function. Coupled with mouse experiments, these results support a major role for claudin-14, a gene associated with kidney stones, in the differential paracellular handling of divalent cations by the renal tubule.

}, keywords = {Animals, Calcium, Claudins, Humans, Kidney Tubules, Magnesium, Polymorphism, Single Nucleotide, Urine}, issn = {1432-2013}, doi = {10.1007/s00424-016-1913-7}, author = {Corre, Tanguy and Olinger, Eric and Harris, Sarah E and Traglia, Michela and Ulivi, Sheila and Lenarduzzi, Stefania and Belge, Hendrica and Youhanna, Sonia and Tokonami, Natsuko and Bonny, Olivier and Houillier, Pascal and Polasek, Ozren and Deary, Ian J and Starr, John M and Toniolo, Daniela and Gasparini, Paolo and Vollenweider, Peter and Hayward, Caroline and Bochud, Murielle and Devuyst, Olivier} } @article {7783, title = {Characterization of 14 novel deletions underlying Rubinstein-Taybi syndrome: an update of the CREBBP deletion repertoire.}, journal = {Hum Genet}, volume = {134}, year = {2015}, month = {2015 Jun}, pages = {613-26}, abstract = {

Rubinstein-Taybi syndrome (RSTS) is a rare, clinically heterogeneous disorder characterized by cognitive impairment and several multiple congenital anomalies. The syndrome is caused by almost private point mutations in the CREBBP (~55\% of cases) and EP300 (~8\%) genes. The CREBBP mutational spectrum is variegated and characterized by point mutations (30-50 \%) and deletions (~10\%). The latter are diverse in size and genomic position and remove either the whole CREBBP gene and its flanking regions or only an intragenic portion. Here, we report 14 novel CREBBP deletions ranging from single exons to the whole gene and flanking regions which were identified by applying complementary cytomolecular techniques: fluorescence in situ hybridization, multiplex ligation-dependent probe amplification and array comparative genome hybridization, to a large cohort of RSTS patients. Deletions involving CREBBP account for 23\% of our detected CREBBP mutations, making an important contribution to the mutational spectrum. Genotype-phenotype correlations revealed that patients with CREBBP deletions extending beyond this gene did not always have a more severe phenotype than patients harboring CREBBP point mutations, suggesting that neighboring genes play only a limited role in the etiopathogenesis of CREBBP-centerd contiguous gene syndrome. Accordingly, the extent of the deletion is not predictive of the severity of the clinical phenotype.

}, keywords = {Adolescent, Adult, Base Sequence, Child, Child, Preschool, Cohort Studies, CREB-Binding Protein, Female, Humans, Infant, Infant, Newborn, Male, Middle Aged, Point Mutation, Rubinstein-Taybi Syndrome, Sequence Deletion}, issn = {1432-1203}, doi = {10.1007/s00439-015-1542-9}, author = {Rusconi, Daniela and Negri, Gloria and Colapietro, Patrizia and Picinelli, Chiara and Milani, Donatella and Spena, Silvia and Magnani, Cinzia and Silengo, Margherita Cirillo and Sorasio, Lorena and Curtisova, Vaclava and Cavaliere, Maria Luigia and Prontera, Paolo and Stangoni, Gabriela and Ferrero, Giovanni Battista and Biamino, Elisa and Fischetto, Rita and Piccione, Maria and Gasparini, Paolo and Salviati, Leonardo and Selicorni, Angelo and Finelli, Palma and Larizza, Lidia and Gervasini, Cristina} } @article {3584, title = {Connexin 26 variant carriers have a better gastrointestinal health: is this the heterozygote advantage?}, journal = {Eur J Hum Genet}, volume = {23}, year = {2015}, month = {2015 May}, pages = {563-4}, issn = {1476-5438}, doi = {10.1038/ejhg.2014.151}, author = {Vuckovic, Dragana and Dallapiccola, Bruno and Franz{\`e}, Annamaria and Mauri, Lucia and Perrone, Maria Dolores and Gasparini, Paolo} } @article {3506, title = {Common variants in UMOD associate with urinary uromodulin levels: a meta-analysis.}, journal = {J Am Soc Nephrol}, volume = {25}, year = {2014}, month = {2014 Aug}, pages = {1869-82}, abstract = {

Uromodulin is expressed exclusively in the thick ascending limb and is the most abundant protein excreted in normal urine. Variants in UMOD, which encodes uromodulin, are associated with renal function, and urinary uromodulin levels may be a biomarker for kidney disease. However, the genetic factors regulating uromodulin excretion are unknown. We conducted a meta-analysis of urinary uromodulin levels to identify associated common genetic variants in the general population. We included 10,884 individuals of European descent from three genetic isolates and three urban cohorts. Each study measured uromodulin indexed to creatinine and conducted linear regression analysis of approximately 2.5 million single nucleotide polymorphisms using an additive model. We also tested whether variants in genes expressed in the thick ascending limb associate with uromodulin levels. rs12917707, located near UMOD and previously associated with renal function and CKD, had the strongest association with urinary uromodulin levels (P<0.001). In all cohorts, carriers of a G allele of this variant had higher uromodulin levels than noncarriers did (geometric means 10.24, 14.05, and 17.67 μg/g creatinine for zero, one, or two copies of the G allele). rs12446492 in the adjacent gene PDILT (protein disulfide isomerase-like, testis expressed) also reached genome-wide significance (P<0.001). Regarding genes expressed in the thick ascending limb, variants in KCNJ1, SORL1, and CAB39 associated with urinary uromodulin levels. These data indicate that common variants in the UMOD promoter region may influence urinary uromodulin levels. They also provide insights into uromodulin biology and the association of UMOD variants with renal function.

}, keywords = {Creatinine, European Continental Ancestry Group, Genetic Variation, Humans, Polymorphism, Single Nucleotide, Uromodulin}, issn = {1533-3450}, doi = {10.1681/ASN.2013070781}, author = {Olden, Matthias and Corre, Tanguy and Hayward, Caroline and Toniolo, Daniela and Ulivi, Sheila and Gasparini, Paolo and Pistis, Giorgio and Hwang, Shih-Jen and Bergmann, Sven and Campbell, Harry and Cocca, Massimiliano and Gandin, Ilaria and Girotto, Giorgia and Glaudemans, Bob and Hastie, Nicholas D and Loffing, Johannes and Polasek, Ozren and Rampoldi, Luca and Rudan, Igor and Sala, Cinzia and Traglia, Michela and Vollenweider, Peter and Vuckovic, Dragana and Youhanna, Sonia and Weber, Julien and Wright, Alan F and Kutalik, Zolt{\'a}n and Bochud, Murielle and Fox, Caroline S and Devuyst, Olivier} } @article {3575, title = {Consanguinity and hereditary hearing loss in Qatar.}, journal = {Hum Hered}, volume = {77}, year = {2014}, month = {2014}, pages = {175-82}, abstract = {

Qatar is a sovereign state located on the Eastern coast of the Arabian Peninsula in the Persian Gulf. Its native population consists of 3 major subgroups: people of Arabian origin or Bedouins, those from an Eastern or Persian ancestry and individuals with African admixture. Historically, all types of consanguineous marriages have been and still are common in the Qatari population, particularly among first and double-first cousins. Thus, there is a higher risk for most inherited diseases including hereditary hearing loss (HHL). In particular, a hearing loss prevalence of 5.2\% has been reported in Qatar, with parental consanguinity being more common among affected individuals as compared with unaffected ones. Our recent molecular results confirm a high homogeneity and level of inbreeding in Qatari HHL patients. Among all HHL genes, GJB2, the major player worldwide, accounts for a minor proportion of cases and at least 3 additional genes have been found to be mutated in Qatari patients. Interestingly, one gene, BDP1, has been described to cause HHL only in this country. These results point towards an unexpected level of genetic heterogeneity despite the high level of inbreeding. This review provides an up-to-date picture of HHL in Qatar and of the impact of consanguinity on this disease.

}, keywords = {Consanguinity, Hearing Loss, Homozygote, Humans, Inheritance Patterns, Pedigree, Prevalence, Principal Component Analysis, Qatar, Transcription Factor TFIIIB}, issn = {1423-0062}, doi = {10.1159/000360475}, author = {Girotto, Giorgia and Mezzavilla, Massimo and Abdulhadi, Khalid and Vuckovic, Dragana and Vozzi, Diego and Khalifa Alkowari, Moza and Gasparini, Paolo and Badii, Ramin} } @article {1802, title = {Contribution of SNP arrays in diagnosis of deletion 2p11.2-p12.}, journal = {Gene}, volume = {492}, year = {2012}, month = {2012 Jan 15}, pages = {315-8}, abstract = {

Deletions of the short arm of chromosome 2 are exceedingly rare, having been reported in few patients. Furthermore most cases with deletion in 2p11.2-p12 have been studied using standard karyotype and so it is not possible to delineate the precise size of deletions. Here, we describe a 9-year-old girl with a 9.4 Mb de novo interstitial deletion of region 2p11.2-p12 identified by SNP array analysis. The deleted region encompasses over 40 known genes, including LRRTM1, CTNNA2 and REEP1, haploinsufficiency of which could explain some clinical features of this patient such as mental retardation, speech delay and gait abnormalities. A comparison of our case with previously reported patients who present deletions in 2p11.2-p12 was carried out. Our case adds new information to the deletion of 2p11.2-p12, improving the knowledge on this rearrangement.

}, keywords = {Abnormalities, Multiple, Child, Chromosomes, Human, Pair 2, Female, Humans, Intellectual Disability, Oligonucleotide Array Sequence Analysis, Polymorphism, Single Nucleotide, Sequence Deletion}, issn = {1879-0038}, doi = {10.1016/j.gene.2011.10.035}, author = {Rocca, Maria Santa and Fabretto, Antonella and Faletra, Flavio and Carlet, Ombretta and Skabar, Aldo and Gasparini, Paolo and Pecile, Vanna} } @article {1660, title = {A case of lymphedema-distichiasis syndrome carrying a new de novo frameshift FOXC2 mutation.}, journal = {Ophthalmic Genet}, volume = {31}, year = {2010}, month = {2010 Jun}, pages = {98-100}, abstract = {

PURPOSE: Lymphedema-Distichiasis (LD, OMIM 153400) is an autosomal dominant disorder with variable expression. The mutated gene implicated is FOXC2, which encodes for a forkhead transcription factor involved in the development of the lymphatic and vascular system. LD is characterized by late childhood or pubertal onset lymphedema of the limbs and distichiasis. Other associations have been reported, including congenital heart disease, ptosis, scoliosis.

CONCLUSIONS: Here we describe a case of LD carrying a de novo frameshift mutation of FOXC2 who presented a prepubertal onset of lower limbs lymphedema and mild distichiasis associated with other anomalies such as webbing neck and ptosis.

}, keywords = {Abnormalities, Multiple, Adolescent, Eye Abnormalities, Eyelashes, Face, Forkhead Transcription Factors, Frameshift Mutation, Humans, Lymphedema, Male, Syndrome}, issn = {1744-5094}, doi = {10.3109/13816811003620517}, author = {Fabretto, Antonella and Shardlow, Alison and Faletra, Flavio and Lepore, Loredana and Hladnik, Uros and Gasparini, Paolo} }