Neonatal lupus is a novel cause of positive newborn screening for X-linked adrenoleukodystrophy.

We report three unrelated individuals, each exposed to maternal autoantibodies during gestation and found to have elevated very long-chain fatty acids (VLCFAs) in the newborn period after screening positive by California newborn screening (NBS) for X-linked adrenoleukodystrophy (ALD). Two probands presented with clinical and laboratory features of neonatal lupus erythematosus (NLE); the third had features suggestive of NLE and a known maternal history of Sjogren's syndrome and rheumatoid arthritis. In all three individuals, subsequent biochemical and molecular evaluation for primary and secondary peroxisomal disorders was nondiagnostic with normalization of VLCFAs by 15 months of age. These cases add to the expanding differential diagnosis to consider in newborns who screen positive for ALD via elevated C26:0-lysophosphatidylcholine. Though the pathophysiology of how transplacental maternal anti-Ro antibodies damage fetal tissue is not well-understood, we postulate that the VLCFA elevations reflect a systemic inflammatory response and secondary peroxisomal dysfunction that improves once maternal autoantibodies wane after birth. Additional evaluation of this phenomenon is warranted to better understand the intricate biochemical, clinical, and possible therapeutic overlap between autoimmunity, inflammation, peroxisomal dysfunction, and human disease.

Phenotypic variability in RERE-related disorders and the first report of an inherited variant.

RERE-related disorders, also known as Neurodevelopmental Disorders with or without Anomalies of the Brain, Eye, or Heart (NEDBEH), are caused by heterozygous pathogenic variants in the arginine-glutamic acid dipeptide repeats gene (RERE). Up-to-date, 20 cases have been reported with the core characteristics of developmental delay, intellectual disability, and/or autism spectrum disorder. Here, we describe three additional cases. In the first case, the patient was found to have a previously reported de novo missense variant; her clinical findings of global developmental delay, intellectual disability, autism spectrum disorder, vision abnormalities, musculoskeletal anomalies, dysmorphic facial features, and a congenital heart defect strengthen existing genotype-phenotype correlations. We also describe the first inherited variant in RERE, found in a patient (case 2) with developmental delay, autism, and hyperopia and his mother (case 3) with ADHD, myopia, and history of mild speech delay. Lastly, by summarizing the clinical features presented in the 23 cases now reported, we provide an updated review of the literature.

Characteristic physical traits of first-grade children in the United States with fetal alcohol spectrum disorders (FASD) and associated alcohol and drug exposures.

We compared growth, physical features, and minor anomalies in 131 first-grade children with fetal alcohol spectrum disorders (FASD) to those of a representative comparison group of typically developing children from the same populations (n = 1212). The data were collected from three regional sites in the NIAAA-funded Collaboration on FASD Prevalence (CoFASP). Dysmorphology examinations were performed by a team of expert clinical geneticists, and FASD diagnoses were assigned according to the Revised Institute of Medicine Guidelines, which include assessments of growth, dysmorphology, neurobehavior, and maternal risk interviews. We present detailed data on 32 physical traits, minor anomalies, and a summary dysmorphology score for children within each of the four diagnostic categories in the continuum of FASD. There were few differences in the frequency of FASD diagnoses by race or Hispanic ethnicity. Children with FASD were born to mothers who reported using alcohol, tobacco (28.3%), and other drugs (14.2%) during pregnancy. Controlling for tobacco and other drug use, risk analysis indicated that women with a drinking pattern of 3 drinks per drinking day prior to pregnancy were 10 times more likely (p < 0.001, OR = 9.92, 95% CI: 4.6-21.5) to bear a child with FASD than those who reported abstinence prior to pregnancy.

The prevalence of fetal alcohol spectrum disorders in rural communities in South Africa: A third regional sample of child characteristics and maternal risk factors.

BACKGROUND: This study is the ninth cross-sectional community study of fetal alcohol spectrum disorders (FASD) conducted by the multidisciplinary Fetal Alcohol Syndrome Epidemiology Research team in the Western Cape Province of South Africa. It is the third comprehensive study of FASD in a rural, agricultural region of South Africa. METHODS: Population-based, active case ascertainment methods were employed among a school-based cohort to assess child physical and neurobehavioral traits, and maternal risk factor interviews were conducted to identify all children with FASD to determine its prevalence. RESULTS: Consent was obtained for 76.7% of 1158 children attending first grade in the region's public schools. Case-control results are presented for 95 with fetal alcohol syndrome (FAS), 64 with partial fetal alcohol syndrome (PFAS), 77 with alcohol-related neurodevelopmental disorder (ARND), 2 with alcohol-related birth defects (ARBD), and 213 randomly-selected controls. Four techniques estimating FASD prevalence from in-person examinations and testing yielded a range of total FASD prevalence of 206-366 per 1000. The final weighted, estimated prevalence of FAS was 104.5 per 1000, PFAS was 77.7 per 1000, ARND was 125.2 per 1000, and total FASD prevalence was 310 per 1000 (95% CI = 283.4-336.7). Expressed as a percentage, 31% had FASD. Although the rate of total FASD remained steady over 9 years, the proportion of children within the FASD group has changed significantly: FAS trended down and ARND trended up. A detailed evaluation is presented of the specific child physical and neurobehavioral traits integral to assessing the full continuum of FASD. The diagnosis of a child with FASD was significantly associated with maternal proximal risk factors such as: co-morbid prenatal use of alcohol and tobacco (OR = 19.1); maternal drinking of two (OR = 5.9), three (OR = 5.9), four (OR = 38.3), or more alcoholic drinks per drinking day; and drinking in the first trimester (OR = 8.4), first and second trimesters (OR = 17.7), or throughout pregnancy (OR = 18.6). Distal maternal risk factors included the following: slight or small physical status (height, weight, and head circumference), lower BMI, less formal education, late recognition of pregnancy, and higher gravidity, parity, and older age during the index pregnancy. CONCLUSION: The prevalence of FASD remained a significant problem in this region, but the severity of physical traits and anomalies within the continuum of FASD is trending downwards.

Bi-allelic ADPRHL2 Mutations Cause Neurodegeneration with Developmental Delay, Ataxia, and Axonal Neuropathy.

ADP-ribosylation is a reversible posttranslational modification used to regulate protein function. ADP-ribosyltransferases transfer ADP-ribose from NAD+ to the target protein, and ADP-ribosylhydrolases, such as ADPRHL2, reverse the reaction. We used exome sequencing to identify five different bi-allelic pathogenic ADPRHL2 variants in 12 individuals from 8 families affected by a neurodegenerative disorder manifesting in childhood or adolescence with key clinical features including developmental delay or regression, seizures, ataxia, and axonal (sensori-)motor neuropathy. ADPRHL2 was virtually absent in available affected individuals' fibroblasts, and cell viability was reduced upon hydrogen peroxide exposure, although it was rescued by expression of wild-type ADPRHL2 mRNA as well as treatment with a PARP1 inhibitor. Our findings suggest impaired protein ribosylation as another pathway that, if disturbed, causes neurodegenerative diseases.

Gestational age and birth growth parameters as early predictors of fetal alcohol spectrum disorders.

OBJECTIVE: To investigate gestational age and growth at birth as predictors of fetal alcohol spectrum disorders (FASD). METHODS: The sample analyzed here comprises 737 randomly selected children who were assessed for growth, dysmorphology, and neurobehavior at 7 years of age. Maternal interviews were conducted to ascertain prenatal alcohol exposure and other maternal risk factors. Birth data originated from clinic records and the data at 7 years of age originated from population-based, in-school studies. Binary linear regression assessed the relationship between preterm birth, small for gestational age (SGA), and their combination on the odds of a specific FASD diagnosis or any FASD. RESULTS: Among children diagnosed with FASD at 7 years of age (n = 255), a review of birth records indicated that 18.4% were born preterm, 51.4% were SGA, and 5.9% were both preterm and SGA. When compared to non-FASD controls (n = 482), the birth percentages born preterm, SGA, and both preterm and SGA were respectively 12.0%, 27.7%, and 0.5%. Mothers of children with FASD reported more drinking during all trimesters, higher gravidity, lower educational attainment, and older age at pregnancy. After controlling for usual drinks per drinking day in the first trimester, number of trimesters of drinking, maternal education, tobacco use, and maternal age, the odds ratio of an FASD diagnosis by age 7 was significantly associated with SGA (OR = 2.16, 95% CI: 1.35 to 3.45). SGA was also significantly associated with each of the 3 most common specific diagnoses within the FASD continuum: fetal alcohol syndrome (FAS; OR = 3.1), partial FAS (OR = 2.1), and alcohol-related neurodevelopmental disorder (OR = 2.0). CONCLUSION: SGA is a robust early indicator for FASD in this random sample of children assessed at 7 years of age.

Immunohistochemical ALK Expression in Granular Cell Atypical Fibroxanthoma: A Diagnostic Pitfall for ALK-Rearranged Non-neural Granular Cell Tumor.

ABSTRACT: Atypical fibroxanthoma (AFX) is a neoplasm that most commonly occurs on sun-damaged skin of the head and neck in elderly patients and that usually exhibits indolent clinical behavior with complete excision. The granular cell variant of AFX demonstrates overlapping histopathologic features with dermal non-neural granular cell tumor (NNGCT), which typically arises on the extremities of young to middle aged adults with rare reports of regional metastasis. A subset of NNGCT harbors ALK rearrangements and expresses ALK by immunohistochemistry. Here, we present 2 cases of granular cell AFX occurring on the scalp of males aged 73 and 87 with ALK expression by immunohistochemistry and no evidence of an ALK rearrangement on fluorescence in situ hybridization, representing a diagnostic pitfall for NNGCT.

Xq22 deletions and correlation with distinct neurological disease traits in females: Further evidence for a contiguous gene syndrome.

Xq22 deletions that encompass PLP1 (Xq22-PLP1-DEL) are notable for variable expressivity of neurological disease traits in females ranging from a mild late-onset form of spastic paraplegia type 2 (MIM# 312920), sometimes associated with skewed X-inactivation, to an early-onset neurological disease trait (EONDT) of severe developmental delay, intellectual disability, and behavioral abnormalities. Size and gene content of Xq22-PLP1-DEL vary and were proposed as potential molecular etiologies underlying variable expressivity in carrier females where two smallest regions of overlap (SROs) were suggested to influence disease. We ascertained a cohort of eight unrelated patients harboring Xq22-PLP1-DEL and performed high-density array comparative genomic hybridization and breakpoint-junction sequencing. Molecular characterization of Xq22-PLP1-DEL from 17 cases (eight herein and nine published) revealed an overrepresentation of breakpoints that reside within repeats (11/17, ~65%) and the clustering of ~47% of proximal breakpoints in a genomic instability hotspot with characteristic non-B DNA density. These findings implicate a potential role for genomic architecture in stimulating the formation of Xq22-PLP1-DEL. The correlation of Xq22-PLP1-DEL gene content with neurological disease trait in female cases enabled refinement of the associated SROs to a single genomic interval containing six genes. Our data support the hypothesis that genes contiguous to PLP1 contribute to EONDT.

Ocular measurements in fetal alcohol spectrum disorders.

Fetal alcohol spectrum disorders (FASD) describe a range of physical, behavioral, and neurologic deficits in individuals exposed to alcohol prenatally. Reduced palpebral fissure length is one of the cardinal facial features of FASD. However, other ocular measurements have not been studied extensively in FASD. Using the Fetal Alcohol Syndrome Epidemiologic Research (FASER) database, we investigated how inner canthal distance (ICD), interpupillary distance (IPD), and outer canthal distance (OCD) centiles differed between FASD and non-FASD individuals. We compared ocular measurement centiles in children with FASD to non-FASD individuals and observed reductions in all three centiles for ICD, IPD, and OCD. However, when our non-FASD children who had various forms of growth deficiency (microcephaly, short-stature, or underweight) were compared to controls, we did not observe a similar reduction in ocular measurements. This suggests that reductions in ocular measurements are a direct effect of alcohol on ocular development independent of its effect on growth parameters, which is consistent with animal models showing a negative effect of alcohol on developing neural crest cells. Interpupillary distance centile appeared to be the most significantly reduced ocular measure we evaluated, suggesting it may be a useful measure to be considered in the diagnosis of FASD.

Fetal Alcohol Spectrum Disorders in a Southeastern County of the United States: Child Characteristics and Maternal Risk Traits.

OBJECTIVE: To detail the characteristic traits of children with fetal alcohol spectrum disorders (FASDs) and maternal risk factors in a southeastern U.S. County. METHODS: Independent samples were drawn from 2 different cohorts of first-grade students. All consented children (49.8%) were measured for height, weight, and head circumference, and those ≤ 25th centile entered the study along with a random sample drawn from all enrolled students. Study children were examined for physical growth, dysmorphology, and neurobehavior, and their mothers were interviewed. RESULTS: Total dysmorphology scores discriminated well the physical traits of children across the FASD continuum: fetal alcohol syndrome (FAS) = 15.8, partial FAS (PFAS) = 10.8, alcohol-related neurobehavioral disorder (ARND) = 5.2, and typically developing controls = 4.4. Additionally, a neurobehavioral battery distinguished children with each FASD diagnosis from controls. Behavioral problems qualified more children for FASD diagnoses than cognitive traits. Significant proximal maternal risk variables were as follows: reports of prepregnancy drinking, drinking in any trimester, and comorbid use of other drugs in lifetime and during pregnancy, especially alcohol and marijuana (14.9% among mothers of children with FASD vs. 0.4% for controls). Distal maternal risks included reports of other health problems (e.g., depression), living unmarried with a partner during pregnancy, and a lower level of spirituality. Controlling for other drug use during pregnancy, having a child diagnosed with a FASD was 17.5 times greater for women who reported usual consumption of 3 drinks per drinking day prior to pregnancy than for nondrinking mothers (p < 0.001, 95% CI = 5.1 to 59.9). There was no significant difference in the prevalence of FASD by race, Hispanic ethnicity, or socioeconomic status. The prevalence of FASD was not lower than 17.3 per 1,000, and weighted estimated prevalence was 49.0 per 1,000 or 4.9%. CONCLUSION: This site had the second lowest rate in the CoFASP study, yet children with FASD are prevalent.

Fetal Alcohol Spectrum Disorders in a Midwestern City: Child Characteristics, Maternal Risk Traits, and Prevalence.

OBJECTIVE: To determine the characteristics of children with fetal alcohol spectrum disorders (FASD) and their mothers in a Midwestern city. METHODS: Case-control samples were drawn from 2 separate first-grade cohorts (combined N = 4,047) in every city school using different methods. In Cohort Sample 1, all consented small children (≤25th centile on height, weight, and/or head circumference) entered the study along with a random sample from all enrolled students. Cohort Sample 2 was drawn totally at random. Child growth, dysmorphology, and neurobehavior were assessed using the Collaboration on FASD Prevalence (CoFASP) criteria, and mothers were interviewed. RESULTS: For the samples combined, 891 children received dysmorphology examinations, and 692 were case-conferenced for final diagnosis. Forty-four children met criteria for FASD. Total dysmorphology scores differentiated diagnostic groups: fetal alcohol syndrome (FAS), 16.7; partial FAS, 11.8; alcohol-related neurodevelopmental disorder (ARND), 6.1; and typically developing controls, 4.2. Neurobehavioral tests distinguished children with FASD from controls, more for behavioral problems than cognitive delay. Children with ARND demonstrated the poorest neurobehavioral indicators. An adjusted regression model of usual prepregnancy drinking indicated that maternal reports of 3 drinks per drinking day (DDD) were significantly associated with a FASD diagnosis (p = 0.020, OR = 10.1, 95% CI = 1.44 to 70.54), as were 5 or more DDD (p < 0.001, OR = 26.47, 95% CI = 4.65 to 150.62). Other significant maternal risk factors included the following: self-reported drinking in any trimester; smoking and cocaine use during pregnancy; later pregnancy recognition and later and less prenatal care; lower maternal weight, body mass index (BMI), and head circumference; and unmarried status. There was no significant difference in FASD prevalence by race, Hispanic ethnicity, or socioeconomic status at this site, where the prevalence of FASD was 14.4 to 41.2 per 1,000 (1.4 to 4.1%). CONCLUSION: This city displayed the lowest prevalence of FASD of the 4 CoFASP sites. Nevertheless, FASD were common, and affected children demonstrated a common, recognizable, and measurable array of traits.

Fetal Alcohol Spectrum Disorders in a Rocky Mountain Region City: Child Characteristics, Maternal Risk Traits, and Prevalence.

OBJECTIVE: To document prevalence and traits of children with fetal alcohol spectrum disorders (FASD) and maternal risk factors in a Rocky Mountain city. METHODS: Variations on active case ascertainment methods were used in 2 first-grade cohorts in all city schools. The consent rate was 59.2%. Children were assessed for physical growth, dysmorphology, and neurobehavior and their mothers interviewed. RESULTS: Thirty-eight children were diagnosed with FASD and compared with 278 typically developing controls. Total dysmorphology scores summarized well the key physical indicators of FASD and defined specific diagnostic groups. On average, children with FASD performed significantly poorer than controls on intellectual, adaptive, learning, attention, and behavioral tasks. More mothers of children with FASD reported drinking prior to pregnancy and in the first and second trimesters, and had partners with drinking problems than mothers of controls; however, reports of comorbid alcohol use and 6 other drugs were similar for mothers of children with FASD and mothers of controls. Mothers of children with FASD were significantly younger at pregnancy, had lower average weight before pregnancy and less education, initiated prenatal clinic visits later, and reported more health problems (e.g., stomach ulcers and accidents). Children with FASD had significantly lower birth weight and more problems at birth, and were less likely to be living with biological mother and father. Controlling for other drug and tobacco use, a FASD diagnosis is 6.7 times (OR = 6.720, 95% CI = 1.6 to 28.0) more likely among children of women reporting prepregnancy drinking of 3 drinks per drinking day (DDD) and 7.6 times (OR = 7.590, 95% CI = 2.0 to 31.5) more likely at 5 DDD. Prevalence of FAS was 2.9-5.8 per 1,000 children, and total FASD was 34.9 to 82.5 per 1,000 children or 3.5 to 8.3% at this site. CONCLUSION: This site had the second highest prevalence of FASD of the 4 Collaboration on FASD Prevalence sites and clearly identifiable child and maternal risk traits.

Mutation update for the SATB2 gene.

SATB2-associated syndrome (SAS) is an autosomal dominant neurodevelopmental disorder caused by alterations in the SATB2 gene. Here we present a review of published pathogenic variants in the SATB2 gene to date and report 38 novel alterations found in 57 additional previously unreported individuals. Overall, we present a compilation of 120 unique variants identified in 155 unrelated families ranging from single nucleotide coding variants to genomic rearrangements distributed throughout the entire coding region of SATB2. Single nucleotide variants predicted to result in the occurrence of a premature stop codon were the most commonly seen (51/120 = 42.5%) followed by missense variants (31/120 = 25.8%). We review the rather limited functional characterization of pathogenic variants and discuss current understanding of the consequences of the different molecular alterations. We present an expansive phenotypic review along with novel genotype-phenotype correlations. Lastly, we discuss current knowledge of animal models and present future prospects. This review should help provide better guidance for the care of individuals diagnosed with SAS.

Acute leukemia in a patient with 15q overgrowth syndrome.

Overgrowth syndromes are rare genetic conditions which present as global or segmental hyperplasia and are sometimes associated with increased risk of malignancy. Trisomy of the terminal portion of 15q which includes the IGFR1 gene, produces a rare overgrowth phenotype that has been termed 15q overgrowth syndrome (15q OGS). Upregulation of IGF1R has long been implicated in oncogenesis of multiple cancer types, including acute leukemias, and has been shown to render cells more susceptible to other transforming events. To date, too few cases of 15q OGS have been reported to identify any cancer predisposition. We present a case of a 34-year-old female with intellectual disability, macrocephaly, and subtle dysmorphic features who was diagnosed with mixed phenotype acute leukemia (lymphoid and myeloid). Prior to initiation of therapy she was referred to medical genetics for further evaluation and was identified as having a chromosomal translocation resulting in a partial trisomy of chromosome 15q, consistent with 15q OGS. A review of the literature for cases of malignancy in individuals with increased copy number of 15q revealed only one other reported patient. Given the small number of reported individuals, we cannot rule out an increased risk of cancer associated with this chromosomal overgrowth syndrome. Although concerns have been raised regarding treatment feasibility in the setting of chromosomal disorders, the reported patient underwent successful treatment with allogeneic hematopoietic stem-cell transplant.

Perinatal distress in 1p36 deletion syndrome can mimic hypoxic ischemic encephalopathy.

1p36 deletion syndrome is a well-described condition with a recognizable phenotype, including cognitive impairment, seizures, and structural brain anomalies such as periventricular leukomalacia (PVL). In a large series of these individuals by Battaglia et al., "birth history was notable in 50% of the cases for varying degrees of perinatal distress." Given the potential for perinatal distress, seizures and PVL, we questioned if this disorder has clinical overlap with hypoxic ischemic encephalopathy (HIE). We reviewed the medical records of 69 individuals with 1p36 deletion to clarify the perinatal phenotype of this disorder and determine if there is evidence of perinatal distress and/or hypoxic injury. Our data provides evidence that these babies have signs of perinatal distress. The majority (59% term; 75% preterm) needed resuscitation and approximately 18% had cardiac arrest. Most had abnormal brain imaging (84% term; 73% preterm) with abnormal white matter findings in over half of patients. PVL or suggestion of "hypoxic insult" was present in 18% of term and 45% of preterm patients. In conclusion, individuals with 1p36 deletion have evidence of perinatal distress, white matter changes, and seizures, which can mimic HIE but are likely related to their underlying chromosome disorder.

Fetal Alcohol Spectrum Disorders in a Pacific Southwest City: Maternal and Child Characteristics.

BACKGROUND: There are limited data on the characteristics of children with fetal alcohol spectrum disorders (FASD) and their mothers from the general population in the United States. METHODS: During the 2012 and 2013 academic years, first-grade children in a large urban Pacific Southwest city were invited to participate in a study to estimate the prevalence of FASD. Children who screened positive on weight, height, or head circumference ≤25th centile or on parental report of developmental concerns were selected for evaluation, along with a random sample of those who screened negative. These children were examined for dysmorphology and neurobehavior and their mothers or collateral sources were interviewed. Children were classified as fetal alcohol syndrome (FAS), partial fetal alcohol syndrome (pFAS), alcohol-related neurodevelopmental disorder (ARND), or No FASD. RESULTS: A total of 854 children were evaluated; 5 FAS, 44 pFAS, 44 ARND, and 761 No FASD. Children with FAS or pFAS were more likely to have dysmorphic features, and 32/49 (65.3%) of those met criteria for neurobehavioral impairment on cognitive measures with or without behavioral deficits. In contrast, 28/44 (63.6%) of children with ARND met criteria on behavioral measures alone. Mothers of FASD children were more likely to recognize pregnancy later, be unmarried, and report other substance use or psychiatric disorders, but did not differ on age, socioeconomic status, education, or parity. Mothers of FASD children reported more drinks/drinking day each trimester. The risk of FASD was elevated with increasing number of drinks/drinking day prior to pregnancy recognition, even at the level of 1 drink per day (adjusted odds ratio 3.802, 95% confidence interval 1.634, 8.374). CONCLUSIONS: Data from this general population sample in a large urban region in the United States demonstrate the variability of expression of FASD and point to risk and protective factors for mothers in this setting.

Heart transplantation in two adolescents with Danon disease.

Danon disease (DD) is an X-linked dominant disorder caused by a mutation in the lysosomal-associated membrane protein-2 (LAMP-2) gene coding for the LAMP-2 protein. We report two cases of successful heart transplantation (HT) in adolescent brothers with DD, including one who was bridged to HT for 34 days with a HeartWare left ventricular assist device. In both patients, the post-transplant course was complicated by profound skeletal muscle weakness that resolved with corticosteroid withdrawal. These cases highlight that both HT and ventricular assist device support are feasible in patients with DD. Corticosteroid use may exacerbate skeletal myopathy, and therefore, steroid minimization may be warranted whenever possible.

RTTN Mutations Cause Primary Microcephaly and Primordial Dwarfism in Humans.

Primary microcephaly is a developmental brain anomaly that results from defective proliferation of neuroprogenitors in the germinal periventricular zone. More than a dozen genes are known to be mutated in autosomal-recessive primary microcephaly in isolation or in association with a more generalized growth deficiency (microcephalic primordial dwarfism), but the genetic heterogeneity is probably more extensive. In a research protocol involving autozygome mapping and exome sequencing, we recruited a multiplex consanguineous family who is affected by severe microcephalic primordial dwarfism and tested negative on clinical exome sequencing. Two candidate autozygous intervals were identified, and the second round of exome sequencing revealed a single intronic variant therein (c.2885+8A>G [p.Ser963(∗)] in RTTN exon 23). RT-PCR confirmed that this change creates a cryptic splice donor and thus causes retention of the intervening 7 bp of the intron and leads to premature truncation. On the basis of this finding, we reanalyzed the exome file of a second consanguineous family affected by a similar phenotype and identified another homozygous change in RTTN as the likely causal mutation. Combined linkage analysis of the two families confirmed that RTTN maps to the only significant linkage peak. Finally, through international collaboration, a Canadian multiplex family affected by microcephalic primordial dwarfism and biallelic mutation of RTTN was identified. Our results expand the phenotype of RTTN-related disorders, hitherto limited to polymicrogyria, to include microcephalic primordial dwarfism with a complex brain phenotype involving simplified gyration.

De novo nonsense mutations in KAT6A, a lysine acetyl-transferase gene, cause a syndrome including microcephaly and global developmental delay.

Chromatin remodeling through histone acetyltransferase (HAT) and histone deactylase (HDAC) enzymes affects fundamental cellular processes including the cell-cycle, cell differentiation, metabolism, and apoptosis. Nonsense mutations in genes that are involved in histone acetylation and deacetylation result in multiple congenital anomalies with most individuals displaying significant developmental delay, microcephaly and dysmorphism. Here, we report a syndrome caused by de novo heterozygous nonsense mutations in KAT6A (a.k.a., MOZ, MYST3) identified by clinical exome sequencing (CES) in four independent families. The same de novo nonsense mutation (c.3385C>T [p.Arg1129∗]) was observed in three individuals, and the fourth individual had a nearby de novo nonsense mutation (c.3070C>T [p.Arg1024∗]). Neither of these variants was present in 1,815 in-house exomes or in public databases. Common features among all four probands include primary microcephaly, global developmental delay including profound speech delay, and craniofacial dysmorphism, as well as more varied features such as feeding difficulties, cardiac defects, and ocular anomalies. We further demonstrate that KAT6A mutations result in dysregulation of H3K9 and H3K18 acetylation and altered P53 signaling. Through histone and non-histone acetylation, KAT6A affects multiple cellular processes and illustrates the complex role of acetylation in regulating development and disease.

Prevalence of Fetal Alcohol Spectrum Disorders in 4 US Communities.

Importance: Fetal alcohol spectrum disorders are costly, life-long disabilities. Older data suggested the prevalence of the disorder in the United States was 10 per 1000 children; however, there are few current estimates based on larger, diverse US population samples. Objective: To estimate the prevalence of fetal alcohol spectrum disorders, including fetal alcohol syndrome, partial fetal alcohol syndrome, and alcohol-related neurodevelopmental disorder, in 4 regions of the United States. Design, Setting, and Participants: Active case ascertainment methods using a cross-sectional design were used to assess children for fetal alcohol spectrum disorders between 2010 and 2016. Children were systematically assessed in the 4 domains that contribute to the fetal alcohol spectrum disorder continuum: dysmorphic features, physical growth, neurobehavioral development, and prenatal alcohol exposure. The settings were 4 communities in the Rocky Mountain, Midwestern, Southeastern, and Pacific Southwestern regions of the United States. First-grade children and their parents or guardians were enrolled. Exposures: Alcohol consumption during pregnancy. Main Outcomes and Measures: Prevalence of fetal alcohol spectrum disorders in the 4 communities was the main outcome. Conservative estimates for the prevalence of the disorder and 95% CIs were calculated using the eligible first-grade population as the denominator. Weighted prevalences and 95% CIs were also estimated, accounting for the sampling schemes and using data restricted to children who received a full evaluation. Results: A total of 6639 children were selected for participation from a population of 13 146 first-graders (boys, 51.9%; mean age, 6.7 years [SD, 0.41] and white maternal race, 79.3%). A total of 222 cases of fetal alcohol spectrum disorders were identified. The conservative prevalence estimates for fetal alcohol spectrum disorders ranged from 11.3 (95% CI, 7.8-15.8) to 50.0 (95% CI, 39.9-61.7) per 1000 children. The weighted prevalence estimates for fetal alcohol spectrum disorders ranged from 31.1 (95% CI, 16.1-54.0) to 98.5 (95% CI, 57.5-139.5) per 1000 children. Conclusions and Relevance: Estimated prevalence of fetal alcohol spectrum disorders among first-graders in 4 US communities ranged from 1.1% to 5.0% using a conservative approach. These findings may represent more accurate US prevalence estimates than previous studies but may not be generalizable to all communities.