Purpose To describe the molecular epidemiology of nonsyndromic retinitis pigmentosa (RP) and Usher syndrome (US) in Italian patients. Methods A total of 591 probands (315 with family history and 276 sporadics) were analyzed. For 155 of them, we performed a family segregation study, considering a total of 382 relatives. Probands were analyzed by a customized multigene panel approach. Sanger sequencing was used to validate all genetic variants and to perform family segregation studies. Copy number variants of selected genes were analyzed by multiplex ligation-dependent probe amplification. Four patients who tested negative to targeted next-generation sequencing analysis underwent clinical exome sequencing. Results The mean diagnostic yield of molecular testing among patients with a family history of retinal disorders was 55.2% while the diagnostic yield including sporadic cases was 37.4%. We found 468 potentially pathogenic variants, 147 of which were unpublished, in 308 probands and 66 relatives. Mean ages of onset of the different classes of RP were autosomal dominant RP, 19.3 ± 12.6 years; autosomal recessive RP, 23.2 ± 16.6 years; X-linked RP, 13.9 ± 9.9 years; and Usher syndrome, 18.9 ± 9.5 years. We reported potential new genotype-phenotype correlations in three probands, two revealed by TruSight One testing. All three probands showed isolated RP caused by biallelic variants in genes usually associated with syndromes such as PERCHING and Senior-Loken or with retinal dystrophy, iris coloboma, and comedogenic acne syndrome. Conclusions This is the largest molecular study of Italian patients with RP in the literature, thus reflecting the epidemiology of the disease in Italy with reasonable accuracy.

IMPORTANCEBiallelic variants in CLN3 lead to a spectrum of diseases, ranging from severe neurodegeneration with retinal involvement (juvenile neuronal ceroid lipofuscinosis) to retina-restricted conditions. OBJECTIVE To provide a detailed description of the retinal phenotype of patients with isolated retinal degeneration harboring biallelic CLN3 pathogenic variants and to attempt a phenotype-genotype correlation associated with this gene defect. DESIGN, SETTING, AND PARTICIPANTS This retrospective cohort study included patients carrying biallelic CLN3 variants extracted from a cohort of patients with inherited retinal disorders (IRDs) investigated at the National Reference Center for Rare Ocular Diseases of the Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts from December 2007 to August 2020. Data were analyzed from October 2019 to August 2020.MAIN OUTCOME AND MEASURES Functional (best-corrected visual acuity, visual field, color vision, and full-field electroretinogram), morphological (multimodal retinal imaging), and clinical data from patients were collected and analyzed. Gene defect was identified by either next-generation sequencing or whole-exome sequencing and confirmed by Sanger sequencing, quantitative polymerase chain reaction, and cosegregation analysis. RESULTSOf 1533 included patients, 843 (55.0%) were women and 690 (45.0%) were men. A total of 15 cases from 11 unrelated families harboring biallelic CLN3 variants were identified. All patients presented with nonsyndromic IRD. Two distinct patterns of retinal disease could be identified: a mild rod-cone degeneration of middle-age onset (n = 6; legal blindness threshold reached by 70s) and a severe retinal degeneration with early macular atrophic changes (n = 9; legal blindness threshold reached by 40s). Eleven distinct pathogenic variants were detected, of which 4 were novel. All but 1, p.(Arg405Trp), CLN3 point variants and their genotypic associations were clearly distinct between juvenile neuronal ceroid lipofuscinosis and retina-restricted disease. Mild and severe forms of retina-restricted CLN3-linked IRDs also had different genetic background.CONCLUSIONS AND RELEVANCE These findings suggest CLN3 should be included in next-generation sequencing panels when investigating patients with nonsyndromic rod-cone dystrophy. These results document phenotype-genotype correlations associated with specific variants in CLN3. However, caution seems warranted regarding the potential neurological outcome if a pathogenic variant in CLN3 is detected in a case of presumed isolated IRD for the onset of neurological symptoms could be delayed.

Purpose: Describing the clinical and genetic features of an ethnically heterogeneous group of (inherited retinal diseases) IRD patients from different underrepresented countries, referring to specialized Italian Hospitals, and expanding the epidemiological spectrum of the IRD in understudied populations.Methods: The patients’ phenotypes underwent were characterized by exhaustive ophthalmological examinations, including morpho-functional testing. Genetic testing was performed using next-generation sequencing (NGS) and gene sequencing panels targeting a specific set of genes, Sanger sequencing and—when necessary—multiplex ligation-dependent probe amplification (MLPA) to better identify the genotype. When possible, segregation analysis was performed in order to confirm unsolved cases.Results: The article reports the results of the phenotypes and genotypes of 123 IRD probands, 69 males and 54 females, mean age 41 (IQR, 54–30) years, disease onset at 13 (IQR, 27.25–5) years. Thirty-three patients out of 123 (26.8%) were Africans (North/Northwest Africa), 21 (17.1%) Asians, 19 (15.4%) Americans (South/Central America) and 50 (40.7%) Europeans (Eastern Europe). Retinitis pigmentosa was the most represented phenotype (56%), followed by cone dystrophy (11%) and Leber congenital amaurosis (7%), while ABCA4 was the most frequently mutated gene (18%), followed by USH2A (9%) and RPGR (5%). About ABCA4 variants found in Stargardt disease, macular and cone dystrophies were predominant in Asian (42%) and European (21%) patients. The most represented inheritance pattern was autosomal recessive, while a higher frequency of homozygous patients versus compound heterozygotes as compared to previous studies on Italian IRD patients was evidenced, reflecting a possible higher frequency of inbreeding marriages.Conclusion: Though limited by the relatively low number of patients, the present paper paints a picture of the clinical and genetic features of IRD patients from understudied ethnic groups referred to Italian specialized hospitals and extended the epidemiological studies on underrepresented world regional areas.

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The purpose of this study was to expand the mutation spectrum by searching the causative mutations in nine Lebanese families with Usher syndrome (USH) using whole-exome sequencing. The pathogenicity of candidate mutations was first evaluated according to their frequency, conservation, and in silico prediction tools. Then, it was confirmed via Sanger sequencing, followed by segregation analysis. Finally, a meta-analysis was conducted to calculate the prevalence of USH genes in the Lebanese population. Three missense mutations, two splice site mutations, and one insertion/deletion were detected in eight of the families. Four of these variants were novel: c.5535C > A; p.(Asn1845Lys) in exon 41 of CDH23, c.7130G > A; p.(Arg2377Gln) in exon 32 of ADGRV1, c.11390-1G > A in USH2A, and c.3999–6A > G in PCDH15. All the identified mutations were shown to be likely disease-causing through our bioinformatics analysis and co-segregated with the USH phenotype. The mutations were classified according to the ACMG standards. Finally, our meta-analysis showed that the mutations in ADGRV1, USH2A, and CLRN1 are the most prevalent and responsible for approximately 75% of USH cases in Lebanon. Of note, the frequency USH type 3 showed a relatively high incidence (23%) compared to the worldwide prevalence, which is around 2–4%. In conclusion, our study has broadened the mutational spectrum of USH and showed a high heterogeneity of this disease in the Lebanese population.

Cardiovascular diseases (CVDs) are a group of disorders that mainly include coronary, cerebrovascular and rheumatic heart diseases [...]

Background and objectives: Vascular Endothelial Growth Factor (VEGF) is an essential regulator of vascular biology. In addition to the well-established role in angiogenesis, circulating VEGF levels were found elevated in severely anemic patients, pointing out that anemia might affect the progression of angiogenesis in malignant and benign diseases through the alteration of VEGF levels. Ten single nucleotide polymorphisms (SNPs) in VEGFA and other loci were shown to explain more than 50% of its circulating levels. This study investigated the association of those ten VEGF-related SNPs with serum iron levels in a general Lebanese population free of chronic diseases (N = 460). Result: We found that the rs10738760 and the body mass index (BMI) were associated with decreased Iron levels (p = 0.002, and p < 0.001, respectively). When taken together, both variables, rs10738760 and BMI, interacted to reduce iron levels (p < 0.001). According to obesity status, the stratification revealed that the effect of rs10738760 was more pronounced in obese than nonobese individuals (p = 0.025). Conclusion: The intergenic SNP rs10738760 is associated with circulating iron levels, and this association depends on BMI status. Although of interest, these results need replication in larger populations from different ancestries.

Editorial on the Research TopicThe genetics of inherited retinal diseases in understudied ethnic groups: Novel associations, challenges, and perspectives Inherited retinal dystrophies (IRDs) cover a broad array of rare retinal diseases with diversify in genetic bases and phenotypes, affecting roughly as many as one in 2,000 individuals (Chen et al., 2021). Night or color blindness, tunnel vision, and later development to total blindness are all common vision impairment manifestations of IRDs that usually worsen with age (Chen et al., 2021). Cases of IRDs may be syndromic if they are coupled with extra-ocular symptoms or nonsyndromic if they are restricted to the eye (Hartong, 2006;Berson, 2006;Dryja, 2006). Interestingly, IRDs include over 20 different phenotypes (Hartong et al., 2006). The age of onset, the rate of progression, and the underlying causal genes may assist in categorizing these distinct phenotypes (Hartong et al., 2006;Perea-Romero et al., 2021). Retinitis pigmentosa (RP) (OMIM 500004), also known as rod-cone dystrophy, is the most common non-syndromic IRD, affecting around 1.5 million individuals globally (Chen et al., 2021). Other non-syndromic forms include cone-rod dystrophies (OMIM 120970), Stargardt disease (OMIM 248200), X-linked retinoschisis (OMIM 312700) and many others. On the other hand, the most common syndromic form is Usher syndrome (USH) (OMIM 276900), a combination of hearing loss and RP (Castiglione and Moller, 2022).Although several genetic studies have identified novel IRDs-associated genes and genetic variations, most of these associations and gene prevalence data were based on cohorts in Western Europe and North America (Smirnov et al., 2021;Colombo et al., 2021). Although the genetic basis of IRDs varies among patient cohorts, even replication for the major findings is still lacking in understudied ethnicities (Jaffal et al., 2021). Growing evidence is continuously showing the importance of better investigating these ethnicities (Amish, Mennonites, Turks, Middle Eastern