Autosomal Dominant Disease Research Articles

Management Targeted Genetic Evaluation of an Idiopathic Neuropathy Cohort Through ATTRv Amyloidosis Screening.

While the reported prevalence of polyneuropathies is 1%-3%, the incidence of hereditary transthyretin amyloidosis in the United States is estimated to be 1 in 100 000 individuals. Polyneuropathies are known to be difficult to treat and lead to significant morbidity. The aim of pain management is symptomatic treatment, with varying approaches to progression prevention being based on the causative pathophysiology.We assessed the prevalence of hereditary amyloid transthyretin variant (ATTRv) amyloidosis, a progressive autosomal dominant multisystem disease caused by the abnormal formation and extracellular deposition of transthyretin protein fibrils in various tissues, in an idiopathic polyneuropathy population by using genetic analysis. Individuals aged 18 and over with an established diagnosis of polyneuropathy, via electromyography testing that was deemed to be idiopathic, at a large, urban neurology clinic consented to an institutional review board-approved protocol for genetic testing. No further exclusions were made regarding age of onset, family history, axonal neuropathy subtype, comorbidities suggestive of ATTRv amyloidosis, etc. Clinical genetic testing was performed on 134 participants via an 81-gene panel associated with inherited neuromuscular disorders or targeted TTR gene sequencing with deletion and duplication analysis. Within our cohort, 38.06% had at least one reportable finding in one of 38 distinct genes, for a total of 76 reported alterations. Four individuals were identified as having a single pathogenic alteration in an autosomal recessive gene, consistent with carrier status for the 4 following disorders: congenital insensitivity to pain with anhidrosis (NTRK1), Charcot-Marie-Tooth disease type IIP (LRSAM1), Brown-Vialetto-Van Laere syndrome type II (SLC52A2), hereditary sensory and autonomic neuropathy type III (IKBKAP). One individual was found to have a variant of uncertain significance (VUS) (p.G103D) in the TTR gene. Precision medicine on the molecular level with genetic testing in the identification of specific neuropathies may provide clinicians with more detailed information for developing a more direct therapeutic and treatment modality for better-targeted management. Further investigation is needed to expand on the knowledge and understanding of the clinical relevance surrounding the alterations found in the genetic evaluation of idiopathic neuropathy.

Endovascular treatment of contained ruptured internal thoracic artery aneurysm mimicking a tumor in a patient with neurofibromatosis type 1: a case report

BackgroundAn internal thoracic artery aneurysm (ITAA) is an exceedingly rare condition, with approximately two-thirds of reported cases being iatrogenic pseudoaneurysms. The remainder are attributed to various causes, including vasculitis, connective tissue disease, and neurofibromatosis type 1 (NF-1). NF-1 is an autosomal dominant disorder characterized by distinct clinical manifestations that occasionally include life-threatening vascular complications. Although NF-1 patients may develop various vascular abnormalities, ruptured ITAA is rarely reported, with only seven published cases.Case presentationA 32-year-old man with NF-1 consulted for a three-day history of persistent left back and upper arm pain. Initial chest radiography indicated left pleural effusion and an opacity at the left lung apex. Computed tomography scan revealed a mass in the left upper mediastinum that was initially suspected to be a tumor. Subsequent contrast-enhanced computed tomography revealed the mass to be a subclavian artery aneurysm. Detailed contrast-enhanced computed tomography with 1-mm slices was performed for surgical planning, identifying the mass as a left ITAA with contained rupture. Given the risk of re-rupture, emergency angiography was performed, which confirmed rupture of the left ITAA without extravasation. The ITAA was successfully treated with multiple microcoils at the proximal and distal ends. The patient had an uneventful recovery and was discharged on the fourth postoperative day.ConclusionsThis case highlights the importance of considering vascular lesions in NF-1 patients who present with pleural effusion. It also emphasizes the challenges in diagnosing ITAA and the effectiveness of thin-slice contrast-enhanced computed tomography scans and endovascular treatment.

Pituitary Neuroendocrine Tumors in Multiple Endocrine Neoplasia.

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal-dominant disorder characterized by tumors of the pituitary, parathyroid, and endocrine-gastrointestinal tract. Pituitary neuroendocrine tumors (PitNETs) occur in about 40% of MEN1 cases, with 10% being the first manifestation. Recent studies show a slight female predominance, with microPitNETs (<1 cm) being more common than macroPitNETs (>1 cm). Functional PitNETs (FPitNETs) are more frequent than non-functional ones (36% to 48%), with prolactinomas being the most common FPitNETs. MEN1-associated PitNETs are often plurihormonal, larger, and more invasive compared to sporadic types, though patient age and FPitNET proportions are similar. MEN1 mutation-negative patients tend to have larger, symptomatic PitNETs at diagnosis. Six patients with MEN1 have been reported to have pituitary carcinomas, including a mutation- negative patient. Treatment approach between PitNETs in MEN1 and sporadic types appears to be similar. PitNETs also occur in MEN4, but their epidemiology is less understood. In patients with a MEN1-like phenotype and negative genetic testing, MEN4 should be considered.

Like Father like Daughter: Surgical Redo Thoracoabdominal Aneurysm Repairs in a Family With Loeys-Dietz Syndrome.

Loeys Dietz Syndrome (LDS) is an autosomal dominant connective tissue disorder resulting from a mutation in the transforming growth factor beta receptor (TGFBR) family of genes. It is commonly associated with the development of aortic aneurysms and dissections. We report the successful open surgical management of thoracoabdominal aneurysms in a father and daughter with Loeys-Dietz Syndrome after failed endovascular repair. The daughter required stent graft explantation, while the stent graft remained in the father. These cases highlight the importance of early genetic testing of both patients and first-degree family members in those with a strong history of aortic disease, even when there is a lack of typical connective tissue disorder associated physical exam findings and open surgical index operations.

Polyneuropathy in Patients with Spinocerebellar Ataxias Types 2, 3, and 10: A Systematic Review.

Spinocerebellar ataxia (SCA) is an autosomal dominant hereditary disease with a low prevalence, for which more than 50 types have been described. This group of neurodegenerative diseases can present as different phenotypes with varying progression rates and clinical manifestations of different severities. Herein, we systematically reviewed existing medical literature to describe the main characteristics of polyneuropathy in patients with SCA types 2, 3, and 10. Using relevant keywords, 16,972 articles were identified from the databases. Of these, 5,329 duplicate studies were excluded before screening. Subsequently, 11,643 studies underwent title and abstract review, of which only 49 were selected for full-text review. Among these, 24 studies were included. The medical literature suggests peripheral neuropathy - probably in a polyneuropathy phenotype - in SCA types 2 and 3. It is not possible to determine whether there is peripheral neuropathy in patients with SCA type 10, as there is only one case series in Mexico that described peripheral neuropathy in this group. Further studies are required to investigate peripheral neuropathy in patients with SCA types 2, 3, and 10. The study and description of a possible statistical association between CAG repeats and SARA scale scores with the presence of peripheral neuropathy are important points requiring assessment in future research.

Contemplating Screening for Protein S Deficiency: To Screen or Not?

Protein S (PS) deficiency is a thrombophilia disorder due to the reduced activity of protein S which regulates coagulation function leading to venous thromboembolism (VTE) event. It is an autosomal dominant disorder whereby it can be heterozygous or homozygous. A positive family history of protein S deficiency is a significant risk factor for developing thromboembolism. We report a case of an infant born to a mother with suspected protein S deficiency. The dilemma is whether we should screen this infant for protein S deficiency. His baseline coagulation profile was normal according to age and had no thrombotic event throughout his neonatal period.

Reticulate acropigmentation of Kitamura in a case of Gorlin-Goltz syndrome − coincidence or association?

Gorlin-Goltz syndrome also known as nevoid basal cell carcinoma syndrome (NBCCS) is a rare, complex hereditary disorder characterized by phenotypic developmental anomalies and postnatal tumors especially basal cell carcinomas (BCCs) and medulloblastomas. It is inherited as autosomal dominant disorder with inactivating mutation in PTCH 1 gene. Reticulate acropigmentation of Kitamura, a rare pigmented genodermatosis has not been described in the literature in association with NBCCS and may be a new finding. Considering the rarity of the disease and its wide clinical spectrum and complications, it is of paramount importance to identity these atypical presentations of the syndrome at an early stage for holistic approach, early intervention, monitoring of basal cell carcinoma, and genetic counselling.

Campomelic dysplasia: a case report

Campomelic dysplasia is a rare, lethal, and autosomal dominant inherited disorder with reversal of sex in genotypic male in two third cases. An eight-month-old phenotypic female infant was admitted with respiratory distress and failure to thrive. She had facial dysmorphism, cleft in soft palate, pectus excavatum deformity, bowing of lower limbs, dimpling at right knee area and bilateral congenital talipes equinovarus deformity. Radiographs shows 11 pairs of ribs, hypoplastic scapula, bowing of bilateral tibia and hypoplastic bilateral fibula. Karyotyping was 46XYchromosome and whole exome sequencing reveals autosomal dominant affecting SOX9 (NM_000346.4) gene, pathogenic variant of c.583C&gt;T (p.Gin195Ter) which is stop gained variant. She was managed according to hospital protocol and discharged. Prenatal diagnosis, genetic counselling and multidisciplinary approach for management of survival cases is important to reduce mortality.

Interferon-Induced Transmembrane Protein 1 (IFITM1) Is Downregulated in Neurofibromatosis Type 1-Associated Malignant Peripheral Nerve Sheath Tumors.

Neurofibromatosis type 1 (NF1), an autosomal dominant genetic disorder, is caused by mutations in the NF1 gene, which encodes the GTPase-activating protein neurofibromin. The pathogenesis of the tumor progression of benign plexiform neurofibromas (PNs) and malignant peripheral nerve sheath tumors (MPNSTs) remain unclear. Here, we found that interferon-induced transmembrane protein 1 (IFITM1) was downregulated in MPNST tissues compared to those in PN tissues from patients with NF1. Overexpression of IFITM1 in NF1-associated MPNST cells resulted in a significant decrease in Ras activation (GTP-Ras) and downstream extracellular regulatory kinase 1/2 (ERK1/2) phosphorylation, whereas downregulation of IFITM1 via treatment with small interfering RNA in normal Schwann cells had the opposite result, indicating that expression levels of IFITM1 are closely associated with tumor progression in NF1. Treatment of MPNST cells with interferon-gamma (IFN-γ) significantly augmented the expression of IFITM1, thereby leading to a decrease in Ras and ERK1/2 activation. Despite the small number of patient samples, these findings may potentially provide a new target for chemotherapy in patients with NF1-associated MPNSTs. In xenograft mice injected with MPNST cells, IFN-γ treatment successfully suppressed tumor progression with increased IFITM1 expression and decreased Ras and ERK1/2 activation in tumor tissues. Collectively, these results suggest that IFITM1 is closely involved in MPNST pathogenesis and that IFN-γ is a good candidate for the therapeutic treatment of MPNSTs in NF1.

An Overview of Familial Hypocalciuric Hypercalcemia

Familial hypocalciuric hypercalcemia (FHH) is one of the rare reasons for hypercalcemia. FHH is an autosomal dominant disease that is inheritable. The most common calcium sensitive receptors (CaSR) develop because of the inactivation of. In addition, they also develop due to the function loss of AP2S1 and GNA11. The FHH sickness is characterized by hypercalcemia, hypocalciuria, the regular or increased level of the parathyroid hormone, and normal renal function. The symptoms of hypercalcemia are usually not observed. It is often diagnosed by calculating the calcium/creatine clearance ratio of a 24-hour urine sample, and then genetically looking at it. FHH is usually a benign disorder, and when symptomatic and rarely complications develop, calcimimetics are used or parathyroidectomy can be performed. In conclusion, FHH is a benign and genetically transmitted, moderate cause of hypercalcemia. It is rare and usually asymptomatic.

Potential roles of voltage-gated ion channel disruption in Tuberous Sclerosis Complex.

Tuberous Sclerosis Complex (TSC) is a lynchpin disorder, as it results in overactive mammalian target of rapamycin (mTOR) signaling, which has been implicated in a multitude of disease states. TSC is an autosomal dominant disease where 90% of affected individuals develop epilepsy. Epilepsy results from aberrant neuronal excitability that leads to recurring seizures. Under neurotypical conditions, the coordinated activity of voltage-gated ion channels keep neurons operating in an optimal range, thus providing network stability. Interestingly, loss or gain of function mutations in voltage-gated potassium, sodium, or calcium channels leads to altered excitability and seizures. To date, little is known about voltage-gated ion channel expression and function in TSC. However, data is beginning to emerge on how mTOR signaling regulates voltage-gated ion channel expression in neurons. Herein, we provide a comprehensive review of the literature describing common seizure types in patients with TSC, and suggest possible parallels between acquired epilepsies with known voltage-gated ion channel dysfunction. Furthermore, we discuss possible links toward mTOR regulation of voltage-gated ion channels expression and channel kinetics and the underlying epileptic manifestations in patients with TSC.

Microcephaly with or without chorioretinopathy, lymphedema, or mental retardation (MCLMR)- the new lacunae: a case report

BackgroundMicrocephaly with or without chorioretinopathy, lymphedema, or mental retardation is a rare autosomal dominant disease caused by mutations in KIF11 which disrupt EG5 protein function, impacting the development and maintenance of retinal and lymphatic structures due to its expression in the retinal photoreceptor cilia. The primary ocular finding in MCLMR is chorioretinopathy. Additional features can include microphthalmia, angle-closure glaucoma, persistent hyperplastic primary vitreous, cataract, pseudo-coloboma, persistent hyaloid artery, and myopic or hypermetropic astigmatism. The appearance of the chorioretinal lesions as white to pinkish, round, non-elevated atrophic areas devoid of blood vessels resembles the lacunae in Aicardy syndrome. Due to the lack of systematic description of the lesions and significant phenotypical variability, there is an impending need for a detailed report of each case.Case presentationA child with microcephaly detected in the third trimester of gestation began her following in the ophthalmology department due to a non-visually significant cataract. Shortly after, she developed nystagmus and large-angle alternating esotropia with cross-fixation. Her fundus initially showed a pallid optic disc and pigmentary changes, developing thereafter retinal lacunae and a retinal fold. Her differential diagnosis accompanied the dynamic changes in her fundus, which included congenital infections, Leber´s Congenital Amaurosis and Aicardy syndrome. At 19 months old, genetic testing identified a heterozygous mutation (c.1159 C > T, p.Arg387*) in the KIF11 gene. The patient underwent bilateral medial rectus muscle recession surgery at 2 years old for persistent esotropia, with significant improvement. Refraction revealed a hyperopic astigmatism in both eyes (+ 0.25 -2.50 × 180 OD and + 0.75 -2.00 × 170 OS). She continues to require right eye patching for 2 hours daily.ConclusionsThis case report expands the phenotypic spectrum of MCLMR by demonstrating a unique combination of retinal features which sheds new light on differential diagnosis from Aicardy syndrome. Our findings emphasize the significant phenotypic variability associated with MCLMR, particularly regarding ocular involvement. This underscores the importance of detailed clinical evaluation and comprehensive reporting of cases to improve our understanding of the disease spectrum and genotype-phenotype correlations.

Immune profiling of premalignant lesions in patients with Peutz-Jeghers syndrome.

Peutz-Jeghers syndrome (PJS), is a rare autosomal dominant hereditary disease characterized by an elevated risk of various cancers. Serine/Threonine Kinase 11 (STK11) gene is a major tumor suppressor crucial for immune evasion with and beyond tumorigenic cells. It has garnered increasing attention in the realm of oncology treatment, particularly in the context of immunotherapy development. This study aimed to assess the suitability of polyps obtained from individuals with PJS, resulting from germline STK11 deficiency, for immunotherapy. Additionally, we seek to identify potential shared mechanisms related to immune evasion between PJS polyps and cancers. To achieve this, we examined PJS polyps alongside familial adenomatous polyposis (FAP) and sporadic polyps. Polyps were compared among themselves and with either the paracancerous tissues or colon cancers. Pathological and gene expression profiling approaches were employed to characterize infiltrating immune cells and assess the expression of immune checkpoint genes. Our findings revealed that PJS polyps exhibited a closer resemblance to cancer tissues than other polyps in terms of their immune microenvironment. Notably, PJS polyps displayed heightened expression of the immune checkpoint gene CD80 and an accumulation of myeloid cells, particularly myeloid-derived suppressor cells (MDSCs). The findings suggest an immunobiological foundation for the increased cancer susceptibility in PJS patients, paving the way for potential immune therapy applications in this population. Furthermore, utilizing PJS as a model may facilitate the exploration of immune evasion mechanisms, benefiting both PJS and cancer patients.

Challenges in the approach to a patient with aortic stenosis and cardiac amyloidosis with ATTR mutation associated with negative scintigraphy - A case report

IntroductionCardiac amyloidosis (CA) poses significant diagnostic and therapeutic challenges. In this case report, we detail a patient with CA due to a rare transthyretin (CA-TTR) mutation, manifesting with negative myocardial scintigraphy and requiring genetic testing for diagnosis. The patient also had severe aortic stenosis (AS), necessitating discussion with a heart team to determine the optimal treatment strategy. Case reportA 70-year-old male with a family history of sudden death was previously diagnosed with third-degree atrioventricular block and treated with a pacemaker. He presented with worsening exertional dyspnoea, and examination revealed a third heart sound, a systolic murmur indicative of AS and bilateral muscular atrophy in the thenar region. Transthoracic echocardiography indicated severe AS and moderate left ventricular dysfunction, with images suggesting infiltrative disease. Pyrophosphate scintigraphy revealed no abnormal cardiac tracer uptake. Cardiac magnetic resonance imaging (MRI) revealed extensive, heterogeneous, subendocardial late gadolinium enhancement in both the atria and ventricles, which was consistent with CA. Genetic testing identified the Phe84Leu mutation in the TTR gene. Following heart team discussions, the patient underwent successful transcatheter aortic valve implantation (TAVI) and remained asymptomatic in follow-up, being monitored at an outpatient clinic specializing in CA and using tafamidis. DiscussionCA-TTR can be an autosomal dominant disease with variable penetrance involving abnormal amyloid protein deposition in tissues and can often be diagnosed noninvasively via myocardial scintigraphy. However, some TTR mutations do not affect scintigraphy results, necessitating genetic testing when clinical suspicion is high, potentially avoiding endomyocardial biopsy. Moreover, AS occurs in up to 16 % of TTR amyloidosis patients, with the conditions mutually exacerbating each other. Recent consensus suggests that TAVI reduces mortality in patients with severe AS and amyloidosis. ConclusionsVarious diagnostic algorithms emphasize the use of myocardial scintigraphy for suspected CA-TTR. Genetic testing is crucial when scintigraphy results are negative, but clinical suspicion remains high, potentially circumventing invasive procedures. Compared with medical management alone, TAVI has been shown to improve quality of life and survival in patients with concurrent severe AS and CA.

Trial to assess the tolerability of using felodipine to upregulate autophagy as a treatment of Huntington’s disease (FELL-HD): a phase II, single-centre, open-label, dose-finding trial protocol

IntroductionHuntington’s disease (HD) is an autosomal dominant neurodegenerative disorder that presents with a progressive movement disorder along with cognitive and psychiatric problems. It is caused by a Cytosine-adenin-guanine (CAG) expansion...

Mosaic SUFU mutation associated with a mild phenotype of multiple hereditary infundibulocystic basal cell carcinoma syndrome.

Multiple hereditary infundibulocystic basal cell carcinoma syndrome (MHIBCC), an autosomal dominant disorder caused by variants in SUFU, is characterized by numerous infundibulocystic basal cell carcinomas (IBCCs). In this report, we present a possible case of mosaic MHIBCC. A 57-year-old woman underwent the removal of four papules on her face, which were diagnosed as IBCCs. Exome sequencing revealed a SUFU c.1022+1G>A mutation within the skin tumor. The same mutation was detected in her blood but at a lower allele frequency. TA cloning revealed that the allele frequency of the mutation in the blood was 0.07. Additionally, tumor assessment revealed loss of heterozygosity (LOH) in chromosome 10, including the SUFU locus. These results indicate the patient had mosaicism for the SUFU mutation in normal tissues, aligning with the mosaic MHIBCC diagnosis. This, combined with LOH, likely contributed to IBCC development. Mosaic MHIBCC may present with milder symptoms. However, it may still increase the risk of developing brain tumors and more aggressive basal cell carcinoma. The possibility of mosaicism should be investigated in mild MHIBCC cases, where standard genetic tests fail to detect SUFU germline variants.

Advances in uromodulin biology and potential clinical applications.

Uromodulin (also known as Tamm-Horsfall protein) is a kidney-specific glycoprotein secreted bidirectionally into urine and into the circulation, and itis the most abundant protein in normal urine. Although the discovery of uromodulin predates modern medicine, its significance in health and disease has been rather enigmatic. Research studies have gradually revealed that uromodulin exists in multiple forms and has important roles in urinary and systemic homeostasis. Most uromodulin in urine is polymerized into highly organized filaments, whereas non-polymeric uromodulin is detected both in urine and in the circulation, and can have distinct roles. The interactions of uromodulin with the immune system, which were initially reported to be a key role of this protein, are now better understood. Moreover, the discovery that uromodulin is associated with a spectrum of kidney diseases, including acute kidney injury, chronic kidney disease and autosomal-dominant tubulointerstitial kidney disease, has further accelerated investigations into the role of this protein. These discoveries have prompted new questions and ushered in a new era in uromodulin research. Here, we delineate the latest discoveries in uromodulin biologyand its emerging roles in modulating kidney and systemic diseases, and consider future directions, including its potential clinical applications.

Anesthetic management in a rare case of clark-baraitser syndrome: Insights and challenges

Clark Baraitser syndrome is a rare autosomal dominant genetic disorder characterized by multiple congenital anomalies and distinctive facial features. These features, including a high arched palate, can complicate airway management. Anaesthetizing an intellectually disabled patient is a challenging task due to lack of communication and understanding, which makes perioperative evaluation difficult. The perioperative management of antiepileptic drug therapy is important for seizure control in these patients. This case report describes the anaesthetic management of 10-year-old child with Clark Baraitser syndrome with bilateral undescended testis posted for orchiopexy.

Acute intermittent porphyria: a disease with low penetrance and high heterogeneity.

Acute intermittent porphyria (AIP) is caused by mutations in the gene encoding hydroxymethylbilane synthase (HMBS), a key enzyme in the heme biosynthesis pathway. AIP is an autosomal dominant disorder characterized by low penetrance and a highly heterogenous clinical presentation. The estimated prevalence of AIP is 5-10 cases per 100,000 persons, with acute attacks manifesting in less than 1% of the at-risk population. This low frequency of attacks suggests significant roles for oligogenic inheritance and environmental factors in the pathogenesis of the disease. In recent years, identification of several modifier genes has advanced our understanding of the factors influencing AIP penetrance and disease severity. This review summarizes these factors including the impact of specific HMBS mutations, oligogenic inheritance, mitochondrial DNA copy number, age, sex, the influence of sex hormones, and the role of environmental factors. Further studies into the etiology of AIP disease penetrance should inform pathogenesis, potentially allowing for the development of more precise diagnostic and therapeutic approaches.

Rescue of Scn5a mis-splicing does not improve the structural and functional heart defects of a DM1 heart mouse model.

Myotonic Dystrophy Type 1 (DM1) is an autosomal dominant multisystemic disorder for which cardiac features, including conduction delays and arrhythmias, are the second leading cause of disease mortality. DM1 is caused by expanded CTG repeats in the 3' untranslated region of the DMPK gene. Transcription of the expanded DMPK allele produces mRNAs containing long tracts of CUG repeats, which sequester the Muscleblind-Like family of RNA binding proteins, leading to their loss-of-function and the dysregulation of alternative splicing. A well-characterized mis-regulated splicing event in the DM1 heart is the increased inclusion of SCN5A exon 6A rather than the mutually exclusive exon 6B that normally predominates in adult heart. As previous work showed that forced inclusion of Scn5a exon 6A in mice recapitulates cardiac DM1 phenotypes, we tested whether rescue of Scn5a mis-splicing would improve the cardiac phenotypes in a DM1 heart mouse model. We generated mice lacking Scn5a exon 6A to force the expression of the adult SCN5A isoform including exon 6B and crossed these mice to our previously established CUG960 DM1 heart mouse model. We showed that correction Scn5a mis-splicing does not improve the DM1 heart conduction delays and structural changes induced by CUG repeat RNA expression. Interestingly, we found that in addition to Scn5a mis-splicing, Scn5a expression is reduced in heart tissues of CUG960 mice and DM1-affected individuals. These data indicate that Scn5a mis-splicing is not the sole driver of DM1 heart deficits and suggest a potential role for reduced Scn5a expression in DM1 cardiac disease.