Elisabetta Pelo

Expression and Function of Gonadotropin-releasing Hormone (GnRH) Receptor in Human Olfactory GnRH-secreting Neurons AN AUTOCRINE GnRH LOOP UNDERLIES NEURONAL MIGRATION

Olfactory neurons and gonadotropin-releasing hormone (GnRH) neurons share a common origin during organogenesis. Kallmanns syndrome, clinically characterized by anosmia and hypogonadotropic hypogonadism, is due to an abnormality in the migration of olfactory and GnRH neurons. We recently characterized the human FNC-B4 cell line, which retains properties present in vivo in both olfactory and GnRH neurons. In this study, we found that FNC-B4 neurons expressed GnRH receptor and responded to GnRH with time- and dose-dependent increases in GnRH gene expression and protein release (up to 5-fold). In addition, GnRH and its analogs stimulated cAMP production and calcium mobilization, although at different biological thresholds (nanomolar for cAMP and micromolar concentrations for calcium). We also observed that GnRH triggered axon growth, actin cytoskeleton remodeling, and a dose-dependent increase in migration (up to 3–4-fold), whereas it down-regulated nestin expression. All these effects were blocked by a specific GnRH receptor antagonist, cetrorelix. We suggest that GnRH, secreted by olfactory neuroblasts, acts in an autocrine pattern to promote differentiation and migration of those cells that diverge from the olfactory sensory lineage and are committed to becoming GnRH neurons.

Familial amyloid polyneuropathy with genetic anticipation associated to a gly47glu transthyretin variant in an Italian kindred

The most frequent localization of amyloid in transthyretin (TTR) mutations is in the peripheral nerve, causing familial amyloid polyneuropathy (FAP). It is generally accompanied by involvement of other organs such as the myocardium and kidney. To date, over 70 TTR point mutations have been reported in literature, with different phenotypes depending on the location of the mutation in the TTR gene. This paper deals with a point mutation in exon 2 position 47 of the TTR gene, encoding the substitution ofgly-cine with glutamate. The mutation was found in an Italian family with 5 patients over 3 generations. The phenotype was characterised by peripheral neuropathy and autonomic dysfunction, associated in some patients with cardiomyopathy and renal involvement. The symptoms were very severe and the patients did not survive long, thus suggesting the aggressive nature of the pathological process. Moreover, in the succeeding generations of this family, there was genetic anticipation in the age of onset of the disease.

Validation of a method for noninvasive prenatal testing for fetal aneuploidies risk and considerations for its introduction in the Public Health System.

Abstract Objective: The aim of this study was to validate noninvasive prenatal testing (NIPT) for fetal aneuploidies by whole-genome massively parallel sequencing (MPS). Methods: MPS was performed on cell-free DNA (cfDNA) isolated from maternal plasma in two groups: a first set of 186 euploid samples and a second set of 195 samples enriched of aneuploid cases (n = 69); digital PCR for fetal fraction (FF) assessment was performed on 178/381 samples. Cases with <10 × 106 reads (n = 54) were excluded for downstream data analysis. Follow-up data (invasive testing results or neonatal information) were available for all samples. Performances in terms of specificity/sensitivity and Z-score distributions were evaluated. Results: All positive samples for trisomy 21 (T21) (n = 43), trisomy 18 (T18) (n = 6) and trisomy 13 (T13) (n = 7) were correctly identified (sensitivity: 99.9%); 5 false positive results were reported: 3 for T21 (specificity = 98.9%) and 2 for T13 (specificity = 99.4%). Besides FF, total cfDNA concentration seems another important parameter for MPS, since it influences the number of reads. Conclusions: The overall test accuracy allowed us introducing NIPT for T21, T18 and T13 as a clinical service for pregnant women after 10 + 4 weeks of gestation. Sex chromosome aneuploidy assessment needs further validation due to the limited number of aneuploid cases in this study.

Defining the diagnostic effectiveness of genes for inclusion in panels: the experience of two decades of genetic testing for hypertrophic cardiomyopathy at a single center

PurposeGenetic testing in hypertrophic cardiomyopathy (HCM) has long relied on Sanger sequencing of sarcomeric genes. The advent of next-generation sequencing (NGS) has catalyzed routine testing of additional genes of dubious HCM-causing potential. We used 19 years of genetic testing results to define a reliable set of genes implicated in Mendelian HCM and assess the value of expanded NGS panels.MethodsWe dissected genetic testing results from 1,198 single-center HCM probands and devised a widely applicable score to identify which genes yield effective results in the diagnostic setting.ResultsCompared with early panels targeting only fully validated sarcomeric HCM genes, expanded NGS panels allow the prompt recognition of probands with HCM-mimicking diseases. Scoring by “diagnostic effectiveness” highlighted that PLN should also be routinely screened besides historically validated genes for HCM and its mimics.ConclusionThe additive value of expanded panels in HCM genetic testing lies in the systematic screening of genes associated with HCM mimics, requiring different patient management. Only variants in a limited set of genes are highly actionable and interpretable in the clinic, suggesting that larger panels offer limited additional sensitivity. A score estimating the relative effectiveness of a given gene’s inclusion in diagnostic panels is proposed.

CFH Y402H polymorphism in Italian patients with age-related macular degeneration, retinitis pigmentosa, and Stargardt disease

ABSTRACT Background: The complement system has been implicated in the pathogenesis of age-related macular degeneration (AMD) and the CFH Y402H polymorphism has been suggested as a major risk factor for AMD. Recent evidences supported the role of inflammation in the pathogenesis of some retinal dystrophies. Aim of this study was to evaluate the prevalence of CFHY402H polymorphism in a group of Italian patients affected by atrophic AMD, Stargardt disease (STGD), or retinitis pigmentosa(RP). Materials and Methods: Our case–control association study included 116 patients with atrophic AMD, 77 with RP, 86 with STGD, and 100 healthy controls. All the patients were evaluated by a standard ophthalmologic examination and OCT. ERG was performed on STGD and RP patients. All the subjects underwent a blood drawing for genetic testing and the CFHY402H polymorphism was genotyped with the TaqMan real-time polymerase chain reaction single nucleotide polymorphism assay. Results: The prevalence of the risk genotype C/C was higher in the AMD group than in controls (p < 0.001). The risk allele C was more frequent in the AMD group than in controls (p < 0.001). The prevalence of the risk genotype was higher in the RP patients than in controls (p < 0.001) and similarly the risk allele C was more frequent in the RP group (p = 0.008). The CFHY402H genotype distribution was not different between patients with STGD and the controls, for the biallelic (p = 0.531) and for the monoallelic (p = 0.318) evaluation. Conclusions: In our series of Italian patients, the CFHY402H genotype is associated with atrophic AMD and RP, but not with STGD. This result may support the hypothesis of a complement system dysregulation in the pathogenesis of AMD and RP

A new ATTR Phe64Ile mutation with late-onset multiorgan involvement

We describe a novel transthyretin mutation in which phenylalanine is replaced with isoleucine in exon 3 at codon 64: Phe64Ile. The mutation was found in an isolated patient and it was not possible to perform a family study. The phenotype included heart and peripheral nerve involvement associated with a possible gastrointestinal and renal involvement.