De novo variants predicting haploinsufficiency for DIP2C are associated with expressive speech delay.

The disconnected (disco)-interacting protein 2 (DIP2) gene was first identified in D. melanogaster and contains a DNA methyltransferase-associated protein 1 (DMAP1) binding domain, Acyl-CoA synthetase domain and AMP-binding sites. DIP2 regulates axonal bifurcation of the mushroom body neurons in D. melanogaster and is required for axonal regeneration in the neurons of C. elegans. The DIP2 homologues in vertebrates, Disco-interacting protein 2 homolog A (DIP2A), Disco-interacting protein 2 homolog B (DIP2B), and Disco-interacting protein 2 homolog C (DIP2C), are highly conserved and expressed widely in the central nervous system. Although there is evidence that DIP2C plays a role in cognition, reports of pathogenic variants in these genes are rare and their significance is uncertain. We present 23 individuals with heterozygous DIP2C variants, all manifesting developmental delays that primarily affect expressive language and speech articulation. Eight patients had de novo variants predicting loss-of-function in the DIP2C gene, two patients had de novo missense variants, three had paternally inherited loss of function variants and six had maternally inherited loss-of-function variants, while inheritance was unknown for four variants. Four patients had cardiac defects (hypertrophic cardiomyopathy, atrial septal defects, and bicuspid aortic valve). Minor facial anomalies were inconsistent but included a high anterior hairline with a long forehead, broad nasal tip, and ear anomalies. Brainspan analysis showed elevated DIP2C expression in the human neocortex at 10-24 weeks after conception. With the cases presented herein, we provide phenotypic and genotypic data supporting the association between loss-of-function variants in DIP2C with a neurocognitive phenotype.

The Association between Sickle Cell Disease and Postpartum Severe Maternal Morbidity.

OBJECTIVE: To compare the risk of severe maternal morbidity (SMM) from the delivery admission to 42 days' postdischarge among persons with sickle cell disease (SCD) to those without SCD. STUDY DESIGN: This retrospective cohort study included deliveries ≥20 weeks' gestation at an urban safety net hospital in Atlanta, GA from 2011 to 2019. The exposure was SCD diagnosis. The outcome was a composite of SMM from the delivery admission to 42 days' postdischarge. SMM indicators as defined by the Centers for Disease Control and Prevention were identified using the International Classification of Diseases, Ninth and Tenth Revisions (ICD-9/10) codes; transfusion of blood products and sickle cell crisis were excluded. RESULTS: Of N = 17,354 delivery admissions, n = 92 (0.53%) had SCD. Persons with SCD versus without SCD had an increased risk of composite SMM (15.22 vs. 2.29%, p < 0.001), acute renal failure (6.52 vs. 0.71%, p < 0.001), acute respiratory distress syndrome (4.35 vs. 0.17%, p < 0.001), puerperal cerebrovascular disorders (3.26 vs. 0.10%, p < 0.001), sepsis (4.35 vs. 0.42%, p < 0.01), air and thrombotic embolism (5.43 vs. 0.10%, p < 0.001), and ventilation (2.17 vs. 0.09%, p < 0.01). Ultimately, those with SCD had an approximately 6-fold higher incidence risk ratio of SMM, which remained after adjustment for confounders (adjusted incidence risk ratio [aIRR]: 5.96, 95% confidence interval [CI]: 3.4-9.19, p < 0.001). Persons with SCD in active vaso-occlusive crisis at the delivery admission had an approximately 9-fold higher risk of SMM up to 42 days' postdischarge compared with those with SCD not in crisis at the delivery admission (incidence: 25.71 vs. 8.77%, p < 0.05; aIRR: 8.92, 95% CI: 4.5-10.04, p < 0.05). Among those with SCD, SMM at the delivery admission was primarily related to renal and cerebrovascular events, whereas most postpartum SMM was related to respiratory events or sepsis. CONCLUSION: SCD is significantly associated with an increased risk of SMM during the delivery admission and through 42 days' postdischarge. Active crisis at delivery further increases the risk of SMM. KEY POINTS: · Sickle cell disease was associated with an approximately 6-fold increased risk of SMM.. · Active vaso-occlusive crisis at delivery was associated with an approximately 9-fold increased risk of SMM.. · 48% of SMM events in persons with SCD occurred postpartum and were respiratory- or sepsis-related..

Haploinsufficiency of the Notch Ligand DLL1 Causes Variable Neurodevelopmental Disorders.

Notch signaling is an established developmental pathway for brain morphogenesis. Given that Delta-like 1 (DLL1) is a ligand for the Notch receptor and that a few individuals with developmental delay, intellectual disability, and brain malformations have microdeletions encompassing DLL1, we hypothesized that insufficiency of DLL1 causes a human neurodevelopmental disorder. We performed exome sequencing in individuals with neurodevelopmental disorders. The cohort was identified using known Matchmaker Exchange nodes such as GeneMatcher. This method identified 15 individuals from 12 unrelated families with heterozygous pathogenic DLL1 variants (nonsense, missense, splice site, and one whole gene deletion). The most common features in our cohort were intellectual disability, autism spectrum disorder, seizures, variable brain malformations, muscular hypotonia, and scoliosis. We did not identify an obvious genotype-phenotype correlation. Analysis of one splice site variant showed an in-frame insertion of 12 bp. In conclusion, heterozygous DLL1 pathogenic variants cause a variable neurodevelopmental phenotype and multi-systemic features. The clinical and molecular data support haploinsufficiency as a mechanism for the pathogenesis of this DLL1-related disorder and affirm the importance of DLL1 in human brain development.

X-linked duplication copy number variation in a familial overgrowth condition.

We describe an overgrowth condition associated with X-linked copy number variation. Three brothers displayed an overgrowth pattern at birth that continued postnatally. Clinical findings included macrocephaly, distinctive facial features, developmental delay and variable clubfoot. Normal fetal growth was noted until the third trimester by Hadlock standards, revealing a late gestational overgrowth pattern. Microarray analysis in the family showed a maternally inherited 680 kb copy number duplication at Xq26.1-q26.2 in all three brothers. Molecular sequencing for known overgrowth conditions including GPC3, Sotos 1 (NSD1), Malan (NFIX), Perlman (DIS3L2), Weaver (EZH2), Opitz-Kaveggia (MED12) loci were negative. BWS IC1 and IC2 methylation and CDKN1C testing was also negative. Normal IGF1 levels excluded X-linked acrogiantism. The duplicated region Xq26.1-q26.2 contained IGSF1 and at least part of the lncRNA FIRRE. IGSF1, a highly expressed pituitary immunoglobulin superfamily gene, was recently implicated in a genome-wide association study of canine size. IGSF1 variants were associated with large canine breeds compared to smaller breeds. Our findings support the hypothesis that an X-linked variant encompassing the IGSF1 region may be associated with body size. Although IGSF1 loss has been noted in human hypothyroidism, this is the first reported phenotype in a family with copy number duplication in the region. Our findings suggest that prenatal evaluation, cross-species evaluation, Mendelian, and GWAS studies may describe a distinctive familial condition and its corresponding phenotypic features.

Developmental and epileptic encephalopathy in two siblings with a novel, homozygous missense variant in SCN1B.

Developmental and epileptic encephalopathies are genetic disorders in which both the developmental disability and the frequent epileptic activity are the effect of a specific gene variant. While heterozygous variants in SCN1B have been described in families with generalized epilepsy with febrile seizures plus, Type 1, only three cases of homozygous, missense variants in SCN1B have been reported in association with autosomal recessive inheritance of a severe developmental and epileptic encephalopathy. We present two siblings who are homozygous for a novel, missense variant in SCN1B, c.265C>T, predicting p.Arg89Cys. The proband is an 11-year-old female with infantile-onset, fever-induced, intractable generalized tonic-clonic seizures, myoclonic seizures, and developmental slowing and autism spectrum disorder occurring later in the course of the disease. Her 4-year-old brother had a similar epilepsy phenotype, but still displays normal development. This variant has not been previously reported in the homozygous state in control databases. The variant was predicted to be damaging and occurred in the vicinity of other epileptic encephalopathy-associated missense variants that are biallelic and located in the extracellular immunoglobulin loop domain of the protein, which mediates interaction of the beta-1 subunit with cellular adhesion molecules. Our report is the first set of siblings with homozygosity for the p.Arg89Cys variant in SCN1B and further implicates biallelic mutations in this gene as a cause of epileptic encephalopathy mimicking Dravet syndrome. Interestingly, the phenotype we observed was milder compared to that previously described in patients with recessive SCN1B mutations.

Predictive value of postwashed total progressively motile sperm count using CASA estimates in 6871 non-donor intrauterine insemination cycles.

PURPOSE: To determine whether postwashed total progressively motile sperm count (TPMSC) obtained by CASA estimates could predict positive pregnancy test result in non-donor IUI cycles. METHODS: Six thousand eight hundred and seventy one (6,871) IUI cycles with non-donor semen were retrospectively analyzed. Patient, cycle characteristics and prewashed and postwashed semen parameters were included in analysis. The main outcome measure was the positive pregnancy test result. RESULTS: The pregnancy rate per cycle (PR/cycle) when postwashed TPMSC is between 0-0.5 million, 0.51-1 million, 1.01-5 million, 5.01-10 million and greater than 10 million were 8.1% (42/520), 14.4 % (41/285), 16.1% (237/1,469), 18.4% (193/1,046) and 18.8% (668/3,551) respectively. The predicted odd of positive pregnancy result is statistically significantly higher when TPMSC is >0.51 million compared to the TPMSC of <0.51 million (OR = 1.68, 95% CI: 1.04-2.71). The predicted odd of positive pregnancy result is greatest when TPMSC is at least 5 million (OR = 2, 95% CI: 1.38 to 2.9). CONCLUSION: TPMSC is an independent predictor of pregnancy test result and TPMSC of half million or greater is adequate to achieve statistically similar pregnancy test results after non-donor IUI cycles.

Association of Sickle Cell Disease With Severe Maternal Morbidity.

OBJECTIVE: To evaluate the association between sickle cell disease (SCD) and severe maternal morbidity (SMM) in a contemporary cohort of deliveries by non-Hispanic Black people. METHODS: We retrospectively examined SMM by using electronic health record data on deliveries by non-Hispanic Black patients between 2011 and 2020 at a single tertiary, public institution. Sickle cell disease was identified during the delivery admission by using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) and International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes. The primary outcome, SMM at delivery hospitalization, was ascertained using ICD-9-CM and ICD-10-CM codes and excluded sickle cell crisis as an indicator of SMM. We also constructed a secondary measure of SMM that excluded deliveries in which blood transfusion was the only indication of SMM. Poisson regression models were used to estimate risk ratios (RRs) and 95% CIs for the associations between SCD and SMM (overall and for individual indicators). Multivariable models adjusted for age, parity, insurance type, chronic conditions (chronic hypertension, diabetes mellitus, obesity), and multiple gestation. RESULTS: Among 17,493 deliveries by non-Hispanic Black patients during the study period, 132 (0.8%) had a diagnosis of SCD. Of those patients, 87 (65.9%, 95% CI 57.2-73.9) with SCD and 2,035 (11.7%), 95% CI 11.2-12.2) without SCD had SMM. Sickle cell disease was associated with increased risk of SMM (87 vs 2,035, adjusted risk ratio [aRR] 5.4, 95% CI 4.6-6.3) and nontransfusion SMM (51 vs 1,057, aRR 6.0, 95% CI 4.6-8.0). Effect estimates were highest for cardiac arrest (3 vs 14, RR 28.2, 95% CI 3.8-209.3), air and thrombotic embolism (14 vs 72, RR 25.6, 95% CI 12.0-54.6), and puerperal cerebrovascular disorders (10 vs 53, RR 24.8, 95% CI 10.2-60.5). CONCLUSION: Sickle cell disease was associated with a more than fivefold increased risk of SMM during the delivery hospitalization. Our data suggest cardiovascular morbidity as the driving major risk. The identification and monitoring of cardiovascular pathology in patients with SCD before and during pregnancy may reduce SMM.

External cephalic version: Success rates with and without nitrous oxide.

BACKGROUND: External cephalic version (ECV) is a technique used to reduce the incidence of cesarean deliveries due to malpresentation. Nitrous oxide is an inhaled analgesic that may be used for pain relief for women undergoing external cephalic version. OBJECTIVE: To compare the conversion rate of non-cephalic to cephalic presentation in ECV with and without nitrous oxide. STUDY DESIGN: A retrospective cohort analysis was performed including all singleton, term gestation ECVs between January 2016 and June 2017 at a single institution. Multivariable logistic regression was used to compare women who had ECV with nitrous oxide versus ECV without nitrous oxide. The primary outcome was successful rate of conversion to cephalic presentation and the secondary outcome was the rate of vaginal delivery. RESULTS: During the study period, 167 women underwent ECV: 77 with nitrous oxide and 90 without nitrous oxide. Of the 77 women who used nitrous oxide, 25 (32.5%) were successful and 17 of these women delivered vaginally (68%). Of the women who underwent ECV without nitrous oxide, 29 (32.2%) successfully converted and 21 of these delivered vaginally (72%). After controlling for confounders, the use of nitrous oxide had no clinically or statistically significant difference on ECV success rates (OR 1.08, 95% CI 0.52-2.23). CONCLUSION: Nitrous oxide does not seem to affect conversion rate to cephalic presentation in ECV. Further studies are needed to determine the impact of nitrous oxide on women's decision to undergo ECV and on patient satisfaction and tolerability.

Vaginal birth after cesarean: Does accuracy of predicted success change from prenatal intake to admission?

BACKGROUND: There are 2 prediction nomograms for vaginal birth after cesarean delivery. The first is based on variables that are available at the first prenatal visit, and the second includes variables at the time of admission. OBJECTIVE: The purpose of this study was to compare the accuracy of prediction scores that are calculated by the intake and admission prediction nomograms in a modern cohort of racially and ethnically diverse women. STUDY DESIGN: This is a retrospective cohort study that analyzed the data for women with at least 1 previous cesarean delivery who attempted a trial of labor from 2007-2016 at a tertiary medical center. Participants were stratified into 3 probability-of-success groups: low (<35%), moderate (35-65%), and high (>65%). The primary outcome was the difference between the intake- and admission-predicted success scores in the 3 groups. Secondary outcomes were characteristics that were associated with successful vaginal birth after cesarean delivery . RESULTS: Of the 614 women included in the analysis, 444 (72.3%) had a successful vaginal birth after cesarean delivery . Predicted vaginal birth after cesarean delivery success rate ranged from 14.4-96.2%. Patients were stratified into 3 groups by intake predicted success rates: low (<35%; n=21), moderate (35-65%; n=136), and high (>65%; n=457). The change in predicted success rates was compared between the intake and admission nomograms. Women in the low and moderate groups improved their prediction score by approximately 7-8% when variables at the time of admission were included. As a result, more than one-half of these women (172/307; 56%) shifted to a higher predicted success group. The admission nomogram, as compared with the intake nomogram, more accurately predicted vaginal birth after cesarean delivery success in all groups. Analysis of admission variables showed that cervical dilation >2 cm compared with a closed cervix was the strongest predictor of successful vaginal birth after cesarean delivery (relative risk, 1.79; 95% confidence interval, 1.11-2.89). CONCLUSION: The admission prediction nomogram was more accurate and showed higher predicted success compared with the intake nomogram for the same cohort. Because prediction scores may improve at the time of admission, additional counseling on the risks and benefits of trial of labor may be helpful at that time.