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The detection of a pathogenic variant in the BRCA1 or BRCA2 gene has medical and psychological consequences for both, affected mutation carriers and their relatives. A two-phase study with explanatory sequential mixed methods design examined the psychological impact of genetic testing and associated family communication processes. Analyzing a survey data of 79 carriers of a BRCA1 or BRCA2 mutation, the majority had general psychological distress independent of cancer diagnosis in the patients' history. The point prevalence of depression was 16.9%. Contrary to their subjective perception, the respondents' knowledge about those mutations was moderate. Despite the high rate of information transfer to relatives at risk (100%), their reported uptake of genetic testing was low (45.6%). Communication about the mutation detection was more frequent with female than with male relatives. In-depth focus group interviews revealed significant barriers to accessing genetic counseling including anxiety, uncertainty about the benefits of testing and about the own cancer risk, particularly among males. This study suggests that an adequate knowledge of the genetic background and psychological support is required to reduce emotional distress, to support familial communication and to facilitate genetic testing. [ABSTRACT FROM AUTHOR]

Infantile nystagmus syndrome (INS) denominates early-onset, involuntary oscillatory eye movements with different etiologies. Nystagmus is also one of the symptoms in oculocutaneus albinism (OCA), a heterogeneous disease mainly caused by defects in melanin synthesis or melanosome biogenesis. Dopachrome tautomerase (DCT, also called TYRP2) together with tyrosinase (TYR) and tyrosin-related protein 1 (TYRP1) is one of the key enzymes in melanin synthesis. Although DCT´s role in pigmentation has been proven in different species, until now only mutations in TYR and TYRP1 have been found in patients with OCA. Detailed ophthalmological and orthoptic investigations identified a consanguineous family with two individuals with isolated infantile nystagmus and one family member with subtle signs of albinism. By whole-exome sequencing and segregation analysis, we identified the missense mutation c.176G > T (p.Gly59Val) in DCT in a homozygous state in all three affected family members. We show that this mutation results in incomplete protein maturation and targeting in vitro compatible with a partial or total loss of function. Subsequent screening of a cohort of patients with OCA (n = 85) and INS (n = 25) revealed two heterozygous truncating mutations, namely c.876C > A (p.Tyr292*) and c.1407G > A (p.Trp469*), in an independent patient with OCA. Taken together, our data suggest that mutations in DCT can cause a phenotypic spectrum ranging from isolated infantile nystagmus to oculocutaneous albinism. [ABSTRACT FROM AUTHOR]

Hypophosphatasia (HPP) is a rare inborn error of metabolism due to a decreased activity of tissue nonspecific alkaline phosphatase (TNSALP). As the onset and severity of HPP are heterogenous, it can be challenging to determine the pathogenicity of detected rare ALPL variants in symptomatic patients. We aimed to characterize patients with rare ALPL variants to propose which patients can be diagnosed with adult HPP. We included 72 patients with (1) clinical symptoms of adult HPP or positive family history and (2) low TNSALP activity and/or high pyridoxal 5'-phosphate (PLP) levels, who underwent ALPL gene sequencing. The patients were analyzed and divided into three groups depending on ALPL variant pathogenicity according to the classification of the American College of Medical Genetics and Genomics (ACMG). Reported pathogenic (n = 34 patients), rare (n = 17) and common (n = 21) ALPL variants only were found. Muscular complaints were the most frequent symptoms (> 80%), followed by bone affection (> 50%). Tooth involvement was significantly more common in patients with pathogenic or rare ALPL variants. Seven rare variants could be classified as likely pathogenic (ACMG class 4) of which five have not yet been described. Inconclusive genetic findings and less specific symptoms make diagnosis difficult in cases where adult HPP is not obvious. As not every pathogenic or rare ALPL variant leads to a manifestation of HPP, only patients with bone complications and at least one additional complication concerning teeth, muscle, central nervous and mental system, repeated low TNSALP activity and high PLP levels should be diagnosed as adult HPP if rare ALPL gene variants of ACMG class 4 or higher support the diagnosis. [ABSTRACT FROM AUTHOR]

On the other hand, two cases of IDH wild type gliomas in LFS patients have only recently been described to harbor I MYCN i amplifications [[2]]. Both tumors have also been analyzed via global DNA methylation profiling and showed significant matches to the DNA methylation classes of glioblastoma, IDH wild type, H3.3 G34 mutant (case 1) and to the methylation class of glioblastoma, IDH wild type, subclass MYCN (case 2, www.molecularneuropathology.org, classifier version 11b4 [[3]]). IDH wild type glioblastomas have recently been observed in three LFS patients [[2]]. [Extracted from the article]

Objective: Spinal and bulbar muscular atrophy (SBMA) is caused by an abnormal expansion of the CAG repeat in the androgen receptor gene. This study aimed to systematically phenotype a German SBMA cohort (n = 80) based on laboratory markers for neuromuscular, metabolic, and endocrine status, and thus provide a basis for the selection of biomarkers for future therapeutic trials.Methods: We assessed a panel of 28 laboratory parameters. The clinical course and blood biomarkers were correlated with disease duration and CAG repeat length. A subset of 11 patients was evaluated with body fat MRI.Results: Almost all patients reported muscle weakness (99%), followed by dysphagia (77%), tremor (76%), and gynecomastia (75%) as major complaints. Creatine kinase was the most consistently elevated (94%) serum marker, which, however, did not relate with either the disease duration or the CAG repeat length. Paresis duration and CAG repeat length correlated with dehydroepiandrosterone sulfate after correction for body mass index and age. The androgen insensitivity index was elevated in nearly half of the participants (48%).Conclusions: Metabolic alterations in glucose homeostasis (diabetes) and fat metabolism (combined hyperlipidemia), and sex hormone abnormalities (androgen insensitivity) could be observed among SBMA patients without association with the neuromuscular phenotype. Dehydroepiandrosterone sulfate was the only biomarker that correlated strongly with both weakness duration and the CAG repeat length after adjusting for age and BMI, indicating its potential as a biomarker for both disease severity and duration and, therefore, its possible use as a reliable outcome measure in future therapeutic studies. [ABSTRACT FROM AUTHOR]

Warburg Micro syndrome and Martsolf syndrome are clinically overlapping autosomal recessive conditions characterized by congenital cataracts, microphthalmia, postnatal microcephaly, and developmental delay. The neurodevelopmental and ophthalmological phenotype is more severe in Warburg Micro syndrome in which cerebral malformations and severe motor and mental retardation are common. While biallelic loss-of-function mutations in RAB3GAP1 are present in the majority of patients with Warburg Micro syndrome; a hypomorphic homozygous splicing mutation of RAB3GAP2 has been reported in a single family with Martsolf syndrome. Here, we report a novel homozygous RAB3GAP2 small in-frame deletion, c.499_507delTTCTACACT (p.Phe167_Thr169del) that causes Warburg Micro syndrome in a girl from a consanguineous Turkish family presenting with congenital cataracts, microphthalmia, absent visually evoked potentials, microcephaly, polymicrogyria, hypoplasia of the corpus callosum, and severe developmental delay. No RAB3GAP2 mutations were detected in ten additional unrelated patients with RAB3GAP1-negative Warburg Micro syndrome, consistent with further genetic heterogeneity. In conclusion, we provide evidence that RAB3GAP2 mutations are not specific to Martsolf syndrome. Rather, our findings suggest that loss-of-function mutations of RAB3GAP1 as well as functionally severe RAB3GAP2 mutations cause Warburg Micro syndrome while hypomorphic RAB3GAP2 mutations can result in the milder Martsolf phenotype. Thus, a phenotypic severity gradient may exist in the RAB3GAP-associated disease continuum (the 'Warburg-Martsolf syndrome') which is presumably determined by the mutant gene and the nature of the mutation. [ABSTRACT FROM AUTHOR]

Mutations in the gene CHN1 have been described in autosomal dominant Duane’s retraction syndrome (DRS) and mutations have been shown to interfere with normal innervation of target eye muscles by oculomotor axons in chick embryos. We screened for CHN1 mutations in patients with various congenital ocular motility disorders. Altogether, 29 patients with different congenital ocular motility disorders and a positive family history of congenital ocular motility disturbances or strabismus or bilateral affection or accompanying congenital disorders were enrolled in this study. DNA samples of patients suffering from DRS ( n = 5), Brown syndrome ( n = 13), other congenital motility disorders of the oblique eye muscles ( n = 6), double elevator palsy ( n = 4), and vertical retraction syndrome ( n = 1) were investigated by direct sequencing of all coding exons of CHN1. In the families of our index patients with DRS, other family members displayed DRS, see-saw nystagmus, infantile esotropia, microtropia, or Brown syndrome, respectively. In the families of our patients with cases of Brown syndrome, bilateral abduction deficiency, infantile esotropia, and unspecified strabismus occurred. The patients with congenital disorders of the oblique muscles and with congenital elevation deficiencies other than Brown syndrome had relatives with ptosis, infantile esotropia, DRS, congenital abduction deficiency, and unspecified forms of strabismus. Thus a considerable intrafamilial overlap between different types of congenital forms of motility disorders and strabismus does exist. No mutations were detected in the CHN1 gene in our patients. In addition to known polymorphisms, we identified four novel heterozygous single-nucleotide substitutions, one in the 5′UTR, two in intronic regions, and one in the coding region leading to a synonymous amino acid substitution. We found no evidence for a causative involvement of CHN1 mutations in congenital ocular motor anomalies different from autosomal dominant Duane’s retraction syndrome and provide further evidence for genetic heterogeneity in familial forms of DRS. [ABSTRACT FROM AUTHOR]