Severe adrenal insufficiency in six neonates with normal newborn screening for CAH.

BACKGROUND: Newborn screening (NBS) reduces the risk of mortality in congenital adrenal hyperplasia (CAH), mainly due to the salt-wasting form of 21-hydroxylase deficiency. There is limited knowledge regarding the results of NBS in non-CAH primary adrenal insufficiency (non-CAH PAI). PATIENTS AND METHODS: Clinical and NBS for CAH data of neonates who were diagnosed with non-CAH PAI between January and December 2022 were examined. RESULTS: Patients (n = 6, 4 females) were presented with severe hyperpigmentation (n = 6), hypoglycemia (n = 4), hyponatremia (n = 3), hyperkalemia (n = 1), respiratory distress syndrome (n = 1) between 3rd hour to 2 months of life. All had normal NBS results. The median first-tier 17-hydroxyprogesterone (17OHP) concentration in NBS for CAH was 0.14 ng/mL (range; 0.05-0.85). Molecular studies revealed biallelic mutations in the MC2R (n = 4; 3 homozygous, 1 compound heterozygous), MRAP (n = 1) and STAR (n = 1) genes. Glucocorticoid with or without mineralocorticoid replacement was initiated once the diagnosis of non-CAH PAI was established. CONCLUSION: Neonates with non-CAH PAI have always normal NBS due to persistently low 17OHP, even when these newborn infants are severely symptomatic for adrenal insufficiency. Clinicians should be alert for signs of adrenal insufficiency in neonates, even if the patient has a 'normal' screening for CAH, so as not to delay diagnosis and treatment. This fact should be kept in mind particularly in countries where these conditions are more common than elsewhere.

Secondary findings in 622 Turkish clinical exome sequencing data.

CES (Clinical Exome Sequencing) is a method that we use to diagnose rare diseases with nonspesific clinical features. Besides primary indication for testing genetic information may be detected about diseases which have not yet emerged. ACMG guidelines recommend to report pathogenic variations in medically actionable 59 genes. In this study we evaluated CES data of 622 cases which were tested for various indications. According to ACMG recommendations 59 genes were screened for reportable variations. The detected variations were reviewed using distinct databases and ACMG variation classification guidelines. Among 622 cases 13 (2.1%) had reportable variations including oncogenetic, cardiogenetic disorders, and malignant hyperthermia susceptibility-related genes. In 15 cases (2.4%) heterozygous pathogenic and likely pathogenic variations were detected in genes showing autosomal recessive inheritance. Ten novel variations causing truncated protein or splicing defect were reported. We detected 11 variations having conflicting interpretations in databases and 30 novel variations, predicted as likely pathogenic via insilico analysis tools which further evaluations are needed. As to our knowledge this is the first study investigating secondary findings in Turkish population. To extract the information that may lead to prevent severe morbidities and mortalities from big data is a valuable and lifesaving effort. Results of this study will contrbute to existing knowledge about secondary findings in exome sequencing and will be a pioneer for studies in Turkish population.

A Rare Presentation of 17α Hydroxylase/17,20 Lyase Deficiency in a Patient with non-Hodgkin's Lymphoma: A Case Report.

17α­hydroxylase/17,20­lyase deficiency (17OHD) is a rare form of congenital adrenal hyperplasia that causes decreased cortisol and sex steroid levels and leads to high production of adrenocorticotropic hormone (ACTH). Although affected patients have absolute cortisol deficiency, they do not show clinical signs of cortisol deficiency or hyperpigmentation. These patients most commonly present with delayed puberty and amenorrhea at late pubertal age. Impaired production of sex steroids leads to ambiguous or female external genitalia in affected 46, XY individuals. In this report, we describe a patient with 17OHD who presented with hyperpigmentation and hypergonodotropic hypogonadism while receiving chemotherapy.

PHARC syndrome which an ultra-rare syndrome with retinitis pigmentosa and cataracts: case report and review of the literature.

BACKGROUND: PHARC syndrome (MIM:612674) is a rare neurodegenerative disorder characterized by demyelinating polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataracts (PHARC). The syndrome is caused by mutations in the ABHD12 gene, which encodes αß-hydrolase domain-containing protein 12 related to endocannabinoid metabolism. PHARC syndrome is one of the rare diseases; so far, only 51 patients have been reported in the literature. METHODS: We evaluated the 25-year-old male patient referred to us due to vision loss, cataracts, and hearing loss. Ophthalmological examinations and genetic analyses were performed using targeted next-generation sequencing. RESULTS: In the genetic analysis, the patient was diagnosed with PHARC syndrome by detecting homozygous (NM_001042472.3): c.871del (p.Tyr291IlefsTer28) novel pathogenic variation in the ABHD12 gene. Following the molecular diagnosis, he was referred to the neurology department for reverse phenotyping and sensorimotor demyelinating polyneuropathy was detected in the neurological evaluation. CONCLUSIONS: In this study, we report a novel variation in ABHD12 gene in the first Turkish-origin PHARC patient. We present this study to contribute genotype-phenotype correlation of PHARC syndrome and emphasize the importance of molecular genetic diagnosis in order to determine the appropriate clinical approach. This report is essential for expanding the phenotypic spectrum in different populations and understanding the genotype-phenotype correlation of PHARC syndrome via novel pathogenic variation in the ABHD12 gene.

Myhre syndrome in adulthood: clinical variability and emerging genotype-phenotype correlations.

Myhre syndrome (MS, MIM 139210) is a rare multisystemic disorder caused by recurrent pathogenic missense variants in SMAD4. The clinical features have been mainly documented in childhood and comprise variable neurocognitive development, recognizable craniofacial features, a short stature with a pseudo-muscular build, hearing loss, thickened skin, joint limitations, diverse cardiovascular and airway manifestations, and increased fibrosis often following trauma or surgery. In contrast, adults with MS are underreported obscuring potential clinical variability. Here, we describe 24 adults with MS, including 17 diagnosed after the age of 18 years old, and we review the literature on adults with MS. Overall, our cohort shows a milder phenotype as well as lower mortality rates compared to what has been published in literature. Individuals with a codon 500 variant in SMAD4 present with a more pronounced neurodevelopmental and systemic phenotype. However, in contrast to the literature, we observe cardiovascular abnormalities in individuals with the p.(Arg496Cys) variant. In addition, we describe scoliosis as a new manifestation and we report fertility in two additional males with the p.(Arg496Cys). In conclusion, our study contributes novel insights into the clinical variability of MS and underscores the importance of variant-specific considerations, and we provide recommendations for the management of MS in adulthood.

A Second Family with Myhre Syndrome Caused by the Same Recurrent SMAD4 Pathogenic Variation (p.Arg496Cys).

Introduction: Myhre syndrome (MS; OMIM #139210) is a rare connective tissue disorder presenting with cardiovascular, respiratory, gastrointestinal, and skeletal system findings. Fewer than 100 patients were reported until recently, and all molecularly confirmed cases had de novo heterozygous gain-of-function mutations in the SMAD4 gene. Dysregulation of the TGF-beta signaling pathway leads to axial and appendicular skeleton, connective tissue, cardiovascular system, and central nervous system abnormalities. Case Presentation: Two siblings, 12 and 9 years old, were referred to us because of intellectual disability, neurodevelopmental delay, and dysmorphic facial features. Physical examination revealed hypertelorism, strabismus, small mouth, prognathism, short neck, stiff skin, and brachydactyly. Discussion: With a clinical diagnosis of MS, the SMAD4 gene was analyzed via Sanger sequencing, and a heterozygous c.1486C>T (p.Arg496Cys) pathogenic variation was detected in both of the siblings. The segregation analysis revealed that the mutation was inherited from the father who displayed a milder phenotype. Among the 90 patients in the literature, one family was reported in which two siblings carried the same variation (p.Arg496Cys), inherited from the severely affected mother. We are reporting the second family which has three affected family members, a father and two children. We report this study to remind the clinicians to be aware of the parental transmission of SMAD4 variations and also evaluate the parents of the Myhre cases.

First Patient Diagnosed as Feingold Syndrome Type 2 with Alport Syndrome and Review of the Current Literature.

Introduction: Feingold syndrome type 2 (FGLDS2) is an ultra-rare genetic disorder characterized by short stature, microcephaly, digital abnormalities, and intellectual disability. Until now, 22 patients have been reported in the literature. FGLDS2 is caused by a germline heterozygous deletion of 13q resulting in haploinsufficiency of the MIR17HG gene. Case report: In the present study, we evaluated clinical, radiological, and genetic analyses of a 10-year-old Turkish-origin girl with short stature, brachydactyly, intellectual disability, hematuria, and proteinuria. Conclusion/Discussion: In the array-CGH analysis, a 15.7-Mb deletion, arr[hg19] 13q22q31.3(78,241,132_93,967,288)×1, was detected, and this alteration was evaluated to be pathogenic. The deletion of this region covering the MIR17HG gene is a potential cause of FGLDS2. Also, at her clinical exome sequencing study, a heterozygous c.2023G>A p.(Gly675Ser) variation was detected in the COL4A5 gene (NM_000495.4) that was likely pathogenic in up-to-date databases. As a result, we report on a patient who has FGLDS2 and Alport syndrome. This is the first report of a Turkish-origin FGLDS2 patient. Reporting new cases expands the range of phenotypes, plays a crucial role in understanding the FGLDS2 pathogenesis, and is important in terms of screening at-risk family members for giving appropriate genetic counseling and preimplantation genetic diagnosis opportunities.

Mutation Spectrum of Familial Adenomatous Polyposis Patients in Turkish Population: Identification of 3 Novel APC Mutations.

BACKGROUND: Familial adenomatous polyposis (OMIM #175100) and MUTYH-associated polyposis (OMIM #608456) are rare cancerprone disorders characterized by hundreds of adenomatous polyps in the colon and rectum, which have a high probability of malignant transformation. Attenuated familial adenomatous polyposis is a variant of familial adenomatous polyposis, which is a term used for the condition in which patients have less than 100 colorectal polyps. Germline heterozygous Adenomatous polyposis coli (APC) and biallelic MUTYH (mutY DNA glycosylase) pathogenic variations are responsible for familial adenomatous polyposis and MUTYH-associated polyposis respectively. The aim of this study is to discuss the clinical manifestations of patients having pathogenic APC and MUTYH variations. METHODS: We included 27 probands who have more than 10 colonic polyps in this study. After evaluation of their clinical and family histories, the probands were screened for APC and MUTYH variations via next generation sequencing. The family members of the probands carrying pathogenic variations were screened via Sanger sequencing. RESULTS: Among 27 probands, pathogenic APC and MUTYH variations were detected in 3 and 6 probands respectively. In the APC gene, 3 novel truncating variations (p.Leu360*, p.Leu1489Phefs*23, and p.Leu912*) were detected in 3 unrelated probands. In the MUTYH gene, only 2 distinct pathogenic variations were detected (p.Pro295Leu and p.Glu480del) in the homozygous or compound heterozygous state. CONCLUSION: In this study, molecular etiology was clarified in 9 familial polyposis patients. The p.Pro295Leu and p.Glu480del variations seem to be common in the Turkish population and may be considered as a first-step genetic test in Turkish familial polyposis patients showing autosomal recessive inheritance. However more studies are needed to reveal the exact frequency of these variations.