Steroidogenic electron-transfer factors and their diseases

Most steroidogenesis disorders are caused by mutations in genes encoding the steroidogenic enzymes, but work in the past 20 years has identified related disorders caused by mutations in the genes encoding the cofactors that transport electrons from NADPH to P450 enzymes. Most P450s are microsomal and require electron donation by P450 oxidoreductase (POR); by contrast, mitochondrial P450s require electron donation via ferredoxin reductase (FdxR) and ferredoxin (Fdx). POR deficiency is the most common and best-described of these new forms of congenital adrenal hyperplasia. Severe POR deficiency is characterized by the Antley-Bixler skeletal malformation syndrome and genital ambiguity in both sexes, and hence is easily recognized, but mild forms may present only with infertility and subtle disorders of steroidogenesis. The common POR polymorphism A503V reduces catalysis by P450c17 (17-hydroxylase/17,20-lyase) and the principal drugmetabolizing P450 enzymes. The 17,20-lyase activity of P450c17 requires the allosteric action of cytochrome b5, which promotes interaction of P450c17 with POR, with consequent electron transfer. Rare b5 mutations are one of several causes of 17,20-lyase deficiency. In addition to their roles with steroidogenic mitochondrial P450s, Fdx and FdxR participate in the synthesis of iron-sulfur clusters used by many enzymes. Disruptions in the assembly of Fe-S clusters is associated with Friedreich ataxia and Parkinson disease. Recent work has identified mutations in FdxR in patients with neuropathic hearing loss and visual impairment, somewhat resembling the global neurologic disorders seen with mitochondrial diseases. Impaired steroidogenesis is to be expected in such individuals, but this has not yet been studied.

COMPARATIVE STUDY BETWEEN COMBINED USE OF INTRACERVICAL FOLEY CATHETER WITH VAGINAL MISOPROSTOL VERSUS VAGINAL MISOPROSTOL FOR MID TRIMESTER ABORTIONS IN PATIENTS WITH PREVIOUS CAESAREAN SECTIONS

Background:There is a gradual increase in second-trimester abortion because of wide scale introduction of prenatal screening programs detecting women whose pregnancies are complicated by serious fetal abnormalities suchas aneuploidy, cardiovascular and skeletal malformation. It constitutes 10-15% of all induced abortions.With the global trend of raised cesarean section rate, obstetricians are faced with the challenge of termination of pregnancy in women with a scarred uterus.Termination of pregnancy in second trimester is associated with much more morbidity and mortality than when it is done in the first trimester. The various methods for second trimester termination of pregnancy are still controversial and the search for the ideal method which is the safest, easiest, cheapest and most effective is still going on. Search for alternative and effective method is the need of hour. In our study, we aimed at assessing the effectiveness and safety of intracervical foleys catheter with vaginal misoprost and comparing it with the vaginal misoprost for mid trimester abortions in patients with previous caesarean. Methods: This was a prospective randomized controlled trial conducted on 108 women undergoing mid trimester abortions at Patna medical college and hospital in 2019. Patients were randomly allocated in 2 groups Group I ( intracervical foleys and Misoprostol group): Intracervical Foley catheter inserted with a standard regimen of moistened misoprostol tablets (200 μg) 6 hourly intravaginally was used. Group II (misoprostol group): moistened misoprostol tablets (200 μg) 6 hourly inserted vaginally. Procedure efficacy (defined as complete abortion within 48 hours of first dose of misoprostol), safety and reduction in side effects ,acceptability, dose of misoprost required were assessed in both the groups. Results:The induction to abortion interval was 24.16 ± 1.52 hours in the combined group compared to 45.76 ± 1.63 hours in the misoprostol group (P value<0.021) with success rate of 96% in the combined group and 80 % in misoprostol group. Total dose of misoprostol required in combined group was (682.33+_ 245) micrograms and (1100 +_ 212) micrograms in misoprost group with p value < 0.001 No significant difference as regard occurrence of advere effects between the two groups. Conclusions:Combined use of intracervical foley catheter and vaginal misoprostol is a novel safe, effective and acceptable method for termination of second trimester in patients with previous caesarean sectionpregnancy.

Slc20a2-Deficient Mice Exhibit Multisystem Abnormalities and Impaired Spatial Learning Memory and Sensorimotor Gating but Normal Motor Coordination Abilities

BackgroundPrimary familial brain calcification (PFBC, OMIM#213600), also known as Fahr’s disease, is a rare autosomal dominant or recessive neurodegenerative disorder characterized by bilateral and symmetrical microvascular calcifications affecting multiple brain regions, particularly the basal ganglia (globus pallidus, caudate nucleus, and putamen) and thalamus. The most common clinical manifestations include cognitive impairment, neuropsychiatric signs, and movement disorders. Loss-of-function mutations in SLC20A2 are the major genetic causes of PFBC.ObjectiveThis study aimed to investigate whether Slc20a2 knockout mice could recapitulate the dynamic processes and patterns of brain calcification and neurological symptoms in patients with PFBC. We comprehensively evaluated brain calcifications and PFBC-related behavioral abnormalities in Slc20a2-deficient mice.MethodsBrain calcifications were analyzed using classic calcium-phosphate staining methods. The Morris water maze, Y-maze, and fear conditioning paradigms were used to evaluate long-term spatial learning memory, working memory, and episodic memory, respectively. Sensorimotor gating was mainly assessed using the prepulse inhibition of the startle reflex program. Spontaneous locomotor activity and motor coordination abilities were evaluated using the spontaneous activity chamber, cylinder test, accelerating rotor-rod, and narrowing balance beam tests.ResultsSlc20a2 homozygous knockout (Slc20a2-HO) mice showed congenital and global developmental delay, lean body mass, skeletal malformation, and a high proportion of unilateral or bilateral eye defects. Brain calcifications were detected in the hypothalamus, ventral thalamus, and midbrain early at postnatal day 80 in Slc20a2-HO mice, but were seldom found in Slc20a2 heterozygous knockout (Slc20a2-HE) mice, even at extremely old age. Slc20a2-HO mice exhibited spatial learning memory impairments and sensorimotor gating deficits while exhibiting normal working and episodic memories. The general locomotor activity, motor balance, and coordination abilities were not statistically different between Slc20a2-HO and wild-type mice after adjusting for body weight, which was a major confounding factor in our motor function evaluations.ConclusionThe human PFBC-related phenotypes were highly similar to those in Slc20a2-HO mice. Therefore, Slc20a2-HO mice might be suitable for the future evaluation of neuropharmacological intervention strategies targeting cognitive and neuropsychiatric impairments.

Congenital heart defects and skeletal malformation syndrome with congenital hemiplegia

Congenital heart defects and skeletal malformation syndrome is very rare syndrome. Most of the patients had germline mutations in ABL1 gene. A 30-year-old gentleman presented with history of congenital heart disease (ventricular septal defect) and skeletal malformations which are typical of CHDSKM. Patient also had congenital hemiplegia which is rare in CHDSKMS. Patient also had lactose intolerance since childhood. Patients were evaluated thoroughly to rule out other causes. Current report is one of the rare case reports of CHDSKMS, only few case reports have been published till now.

Heterozygous deletion of Sox9 in mouse mimics the gonadal sex reversal phenotype associated with campomelic dysplasia in humans

Heterozygous mutations in the human SOX9 gene cause the skeletal malformation syndrome campomelic dysplasia which in 75% of 46,XY individuals is associated with male-to-female sex reversal. While studies in homozygous Sox9 knockout mouse models confirmed that SOX9 is critical for testis development, mice heterozygous for the Sox9-null allele were reported to develop normal testes. This led to the belief that the SOX9 dosage requirement for testis differentiation is different between humans, which often require both alleles, and mice, in which one allele is sufficient. However, in prior studies, gonadal phenotypes in heterozygous Sox9 XY mice were assessed only by either gross morphology, histological staining or analyzed on a mixed genetic background. In this study, we conditionally inactivated Sox9 in somatic cells of developing gonads using the Nr5a1-Cre mouse line on a pure C57BL/6 genetic background. Section and whole-mount immunofluorescence for testicular and ovarian markers showed that XY Sox9 heterozygous gonads developed as ovotestes. Quantitative droplet digital PCR confirmed a 50% reduction of Sox9 mRNA as well as partial sex reversal shown by an upregulation of ovarian genes. Our data show that haploinsufficiency of Sox9 can perturb testis development in mice, suggesting that mice may provide a more accurate model of human disorders/differences of sex development (DSD) than previously thought.

Radiographic Recognition of Tarsal Malformation in 8- to 9-Week-Old Bernese Mountain Dogs

Introduction Tarsal malformation is a skeletal malformation of unknown aetiology associated with a variety of morphologic changes to the tarsal and metatarsal bones of the dog. Objective The aim of this study was to determine if early diagnosis and prevalence of tarsal malformation could be obtained at approximately 8 to 9 weeks of age in multiple litters of Bernese Mountain dogs. Methods A prospective study of 51 Bernese Mountain dog puppies were evaluated from 12 litters in northern Italy. Dorsoplantar radiographic views of the tarsus were obtained at 60 ± 5 days of age. Tarsal malformation was defined as an abnormal extension of the central tarsal bone on its medial side, or the presence of ectopic bone located medially to the central tarsal bone, talus and second metatarsal bones (proximomedial, distomedial and metatarsal ossification sites respectively). Results All puppies were found to be clinically normal. Thirty-nine of the 51 puppies showed ossification sites medial to the tarsus as defined. A metatarsal ossification was present in all dogs with either a proximo- or distomedial ossification site. No central tarsal bone extensions were observed. The remainder of the tarsometatarsal joints were normal. Clinical Significance Tarsal malformation can be identified in the 8- to 9-week-old Bernese Mountain dog. The clinical significance of tarsal malformation remains to be determined, either as an incidental finding or a precursor to the development of other clinically relevant and related issues in the tarsus.

Abstract 489: Identification And In-silico Analysis Of Pathogenic Non-synonymous Snps Of Human Sos1 Protein In Noonan Syndrome

Introduction: Noonan syndrome is a genetic disorder (autosomal dominant) characterized by short stature, congenital heart disease, bleeding problems, developmental delays, and skeletal malformation. It is mainly caused by a single nucleotide alteration in four genes PTPN11, SOS1, RAF1, and KRAS . In this study, we computationally analyzed the SOS1 gene to identify the pathogenic non-synonymous single nucleotide polymorphisms (nsSNPs), which is known to cause Noonan syndrome. Hypothesis: We hypothesize that in-silico analysis of human SOS1 mutations in Noonan syndrome would be a promising predictor to study the post-translational modifications. Methods and Results: The variant information of SOS1 was collected from the dbSNP database and the literature review on Noonan syndrome. They were further analyzed by in-silico tools such as I-Mutant, iPTREE-STAB, and MutPred for their structural and functional properties. We found that 11 nsSNPs are more pathogenic for Noonan syndrome. The 3D comparative protein of 11 nsSNPs with its wild-type SOS1 was modeled by using I-Tasser and validated via ERRAT and RAMPAGE. The protein-protein interactions of SOS1, GATA4, TNNT2, and ACTN2 were analyzed using STRING, which showed that HRAS was intermediate between SOS1 and ACTN2 (Fig. 1) . Conclusion: This is the first in-silico study of the SOS1 variant with Noonan syndrome. We proposed that this 11 nsSNPs are the most pathogenic variant of SOS1 , which helps to screen the Noonan patient. Furthermore, our results are promising to study the gain/loss of post-translational modification (PTM) by mutation in cardiac genes and helps to explore the novel molecular pathways.$graphic_{DB5B0E7D-4DA6-4569-A16F-E05B2C9C4D2F}$$

Perinatal severe hypophosphatasia: a case report

ObjectivesHypophosphatasia is a rare, inherited metabolic disorder characterized by low serum alkaline phosphatase activity. It is caused by mutations in the ALPL gene, which encodes tissue-nonspecific alkaline phosphatase (TNSALP) [1], [2], [3]. The degree of skeletal malformation varies, but the severe form carries a very poor prognosis.Case presentationThis study reports a male neonate diagnosed with infantile hypophosphatasia (HPP). Genetic analysis showed two heterozygous missense variants at nucleotides c.977G>T (protein Gly326Val) and c.862+4A>G (IVS8+4A>G) (protein NA). The two mutations originated separately from the parents, consistent with autosomal recessive infantile HPP. The pathogenic variant was ALPL exon-9-heterozygous, and the other allele was ALPL IVS8-heterozygous, a variant of uncertain significance.ConclusionsThis case of infantile HPP was caused by two heterozygous mutations. One of those is a novel genetic mutation needed for further study. Genetic consultation is recommended for future offspring of affected parents.

Rare manifestations of Potter Sequence: A Case Report

Potter sequence is a rare congenital malformation that primarily affects male fetuses and is characterized by pulmonary hypoplasia, skeletal malformation, and kidney abnormalities. The pressure of the uterine wall due to oligohydramnios leads to an unusual facial appearance, abnormal limbsor limbs in abnormal positions or contractures. The fetus generally dies soon after birth due to respiratory insufficiency. We presented a male baby of 35 wks gestation with birth weight 1200gms delivered by primi mother. She had severe oligohydramnios and virtually there was no liquor during birth. The baby had severe perinatal depression at birth requiring resuscitation. Multiple congenital anomalies like absence of left eye, congenital cataract on the right eye, right-sided choanal atresia, micrognathia, low set ears, beaked nose, bilateral clubbed foot with hip deformity were noted. After 2 hours of life,baby developed fast breathing and cyanosis and died due to respiratory failure.

P450 Oxidoreductase Deficiency: A Systematic Review and Meta-analysis of Genotypes, Phenotypes, and Their Relationships

Context P450 oxidoreductase deficiency (PORD) is a rare genetic disorder that is associated with significant morbidity. However there has been limited analysis of reported PORD cases. Objective To determine, based on the cohort of reported PORD cases, genotype-phenotype relationships for skeletal malformations, maternal virilisation in pregnancy, adrenal insufficiency, and disorders of sexual development (DSD). Data Sources PubMed and Web of Science from January 2004 to February 2018. Study Selection Published case reports/series of patients with PORD. Eligible patients were unique, had biallelic mutations, and their clinical features were reported. Data Extraction Patient data were manually extracted from the text of case reports/series. A malformation score, representing the severity of skeletal malformations, was calculated for each patient. Data Synthesis Of the 211 patients published in the literature, 90 were eligible for inclusion. More than 60 unique mutations were identified in this cohort. Four groups of mutations were identified, through regression modeling, as having significantly different skeletal malformation scores. Maternal virilization in pregnancy, reported for 21% of patients, was most common for R457H mutations. Adrenal insufficiency occurred for the majority of patients (78%) and was typically mild, with homozygous R457H mutations being the least deficient. DSD affected most patients (72%), but were less common for males (46XY) with homozygous R457H mutations. Conclusions PORD is a complex disorder with many possible mutations affecting a large number of enzymes. By analyzing the cohort of reported PORD cases, this study identified clear relationships between genotype and several important phenotypic features.