The identified "protective" and "risk" factors, as well as the proposed classification system, represent helpful tools for clinical management and follow-up of patients with multiple hereditary exostoses; moreover, homogeneous cohorts of patients, useful for studies on the pathogenesis of multiple hereditary exostoses, have been identified.
Osteogenesis imperfecta (OI) is a rare genetic disorder of the connective tissue and 90% of cases are due to dominant mutations in COL1A1 and COL1A2 genes. To increase OI disease knowledge and contribute to patient follow-up management, a homogeneous Italian cohort of 364 subjects affected by OI types I–IV was evaluated. The study population was composed of 262 OI type I, 24 type II, 39 type III, and 39 type IV patients. Three hundred and nine subjects had a type I collagen affecting function mutations (230 in α1(I) and 79 in α2(I)); no disease-causing changes were noticed in 55 patients. Compared with previous genotype–phenotype OI correlation studies, additional observations arose: a new effect for α1- and α2-serine substitutions has been pointed out and heart defects, never considered before, resulted associated to quantitative mutations (P = 0.043). Moreover, some different findings emerged if compared with previous literature; especially, focusing the attention on the lethal form, no association with specific collagen regions was found and most of variants localized in the previously reported “lethal clusters” were causative of OI types I–IV. Some discrepancies have been highlighted also considering the “50–55 nucleotides rule,” as well as the relationship between specific collagen I mutated region and the presence of dentinogenesis imperfecta and/or blue sclera. Despite difficulties still present in defining clear rules to predict the clinical outcome in OI patients, this study provides new pieces for completing the puzzle, also thanks to the inclusion of clinical signs never considered before and to the large number of OI Italian patients.
This study provides evidence that using polyurethane foam to prevent sores even inside plaster casts in populations at most risk is a simple and cost-effective strategy and decreases the discomfort, pain and risks in these patients.
Collagen type I mutations are related to wide phenotypic expressions frequently causing an overlap of clinical manifestations, in particular between Osteogenesis Imperfecta (OI) and Ehlers-Danlos syndrome (EDS). Both disorders present inter- and intra-familial clinical variability and several clinical signs are present in both diseases. Recently, after the observation that some individuals first ascertained by a suspicion of EDS resulted then carriers of pathogenic variants of genes known to primarily cause OI, some authors proposed the term “COL1-related overlap disorder” to describe these cases. In this paper, we report clinical, molecular, and biochemical information about an individual with a diagnosis of EDS with severe joint hypermobility who carries a pathogenic heterozygous variant in COL1A2 gene, and a benign variant in COL1A1 gene. The pathogenic variant, commonly ascribed to OI, as well as the benign variant, has been inherited from the individual's mother, who presented only mild signs of OI and the diagnosis of OI was confirmed only after molecular testing. In addition, we reviewed the literature of similar cases of overlapping syndromes caused by COL1 gene mutations. The reported case and the literature review suggest that the COL1-related overlap disorders (OI, EDS and overlapping syndromes) represent a continuum of clinical phenotypes related to collagen type I mutations. The spectrum of COL1-related clinical manifestations, the pathophysiology and the underlying molecular mechanisms support the adoption of the updated proposed term “COL1-related overlap disorder” to describe the overlapping syndromes.
The antiemetic efficacy of granisetron, ondansetron and tropisetron was evaluated in patients treated with cisplatin-Adriamycin (CDP/ADM) and ifosfamide (IFO) by continuous infusion (CI). In all, 90 patients with osteosarcoma were randomly assigned to receive granisetron (2 mg/m2), or ondansetron (5.3 mg/m2), or tropisetron (3.3 mg/m2) plus dexamethasone 8 mg/m2. Chemotherapy consisted of CDP (120 mg/m2, 48-h CI) followed by ADM (75 mg/m2, 24-h CI) and then, in the second cycle, delivered 3 weeks later, IFO 15 g/m2 (120-h CI). Complete protection (CP) from emesis was obtained on 59% of the 717 days of treatment, without significant differences among the three study drugs. A significantly higher rate of CP was obtained during chemotherapy with IFO than with CDP/ ADM (69% vs 44%; P<0.0001). The rate of CP declined from the first to the last day of treatment for both CDP/ADM (61% to 27%, P<0.0001) and IFO (95% to 43%) cycles (P<0.0001). When CDP/ ADM and IFO are delivered on multiple days by CI, granisetron, ondansetron and tropisetron have the same antiemetic efficacy, which declines from the first day onward through successive days.
Background
Stickler Syndrome is a rare connective tissue disorder, characterized by clinical, and genetic heterogeneity. The clinical expression is highly variable, including moderate to severe myopia in childhood, hearing loss, facial dysmorphic features, cleft palate, and early osteoarthritis. COL2A1, COL11A1, and COL11A2 mutations account of the majority of autosomal dominant Stickler Syndrome and, in particular, a heterozygous mutation in COL11A1 gene is identified in about 10 to 20% of Stickler Syndrome patients.
Methods
Herein, we report a case of an 8‐year‐ old child with Stickler Syndrome, presenting with early‐onset of myopia with vitreal abnormalities, facial dysmorphic characteristics, and mild hearing loss later in childhood. To identify the underlying genetic cause, Whole Exome Sequencing was carried out for COL11A1 gene.
Results
A novel de novo heterozygous splice site variant (NM_001854: c.1845 + 5G> C) of the COL11A1 gene, which had not been previously reported, was identified by Whole Exome Sequencing.
Conclusion
We reported a novel COL11A1 mutation in a child with Stickler Syndrome presenting a phenotype of early‐onset of ocular anomalies and mild hearing loss later in childhood. Our findings confirm the variability of the expression of the disease, even in the contest of the same gene‐related disorder, thus, contributing to improve the knowledge on clinical and molecular basis of this rare disease.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.