A second cohort of CHD3 patients expands the molecular mechanisms known to cause Snijders Blok-Campeau syndrome.

There has been one previous report of a cohort of patients with variants in Chromodomain Helicase DNA-binding 3 (CHD3), now recognized as Snijders Blok-Campeau syndrome. However, with only three previously-reported patients with variants outside the ATPase/helicase domain, it was unclear if variants outside of this domain caused a clinically similar phenotype. We have analyzed 24 new patients with CHD3 variants, including nine outside the ATPase/helicase domain.

A contiguous microdeletion syndrome at Xp23.13 with non-obstructive azoospermia and congenital cataracts.

Non-obstructive azoospermia accounts for 10-15% of male infertility, resulting in 60% of all cases of azoospermia and affecting about 1% of the male population. About 30% of these cases are due to Y chromosome microdeletions, chromosome abnormalities, or hormonal disorders. Pathogenic variants in genes on the sex chromosomes have key roles in spermatogenic failure.

Identification of a dominant MYH11 causal variant in chronic intestinal pseudo-obstruction: Results of whole-exome sequencing.

Chronic Intestinal Pseudo-Obstruction (CIPO) is a rare gastrointestinal disorder, which affects the smooth muscle contractions of the gastrointestinal tract. Dominant mutations in the smooth muscle actin gene, ACTG2, accounts for 44%-50% of CIPO patients. Other recessive or X-linked genes, including MYLK, LMOD1, RAD21, MYH11, MYL9, and FLNA were reported in single cases.

The ARID1B spectrum in 143 patients: from nonsyndromic intellectual disability to Coffin-Siris syndrome.

Purpose: Pathogenic variants in ARID1B are one of the most frequent causes of intellectual disability (ID) as determined by large-scale exome sequencing studies. Most studies published thus far describe clinically diagnosed Coffin-Siris patients (ARID1B-CSS) and it is unclear whether these data are representative for patients identified through sequencing of unbiased ID cohorts (ARID1B-ID). We therefore sought to determine genotypic and phenotypic differences between ARID1B-ID and ARID1B-CSS.

CHARGE and Kabuki Syndromes: Gene-Specific DNA Methylation Signatures Identify Epigenetic Mechanisms Linking These Clinically Overlapping Conditions.

Epigenetic dysregulation has emerged as a recurring mechanism in the etiology of neurodevelopmental disorders. Two such disorders, CHARGE and Kabuki syndromes, result from loss of function mutations in chromodomain helicase DNA-binding protein 7 (CHD7) and lysine (K) methyltransferase 2D (KMT2D), respectively. Although these two syndromes are clinically distinct, there is significant phenotypic overlap.

Diagnosis of Chronic Intestinal Pseudo-obstruction and Megacystis by Sequencing the ACTG2 Gene.

Objectives: The diagnosis of chronic intestinal pseudo-obstruction has depended on clinical features, manometry, and imaging. This report aimed to determine the efficacy of sequencing the actin γ-2 (ACTG2) gene for diagnosis. In addition, the goal was to determine how often a mutation would be found in our randomly collected cohort of probands and those probands published previously.

Dental issues in lacrimo-auriculo-dento-digital syndrome: An autosomal dominant condition with clinical and genetic variability.

Background And Overview: Lacrimo-auriculo-dento-digital (LADD) syndrome is an autosomal dominant disorder with variable lacrimal and salivary gland hypoplasia and aplasia, auricular anomalies and hearing loss, dental defects and caries, and digital anomalies.

Case Description: The authors present the cases of 2 unrelated children with enamel defects and history of dry mouth leading to recurrent dental caries. The referring diagnoses were Sjögren disease and hypohidrotic ectodermal dysplasia, respectively.

The Genetics of Benign Paroxysmal Torticollis of Infancy: Is There an Association With Mutations in the CACNA1A Gene?

Benign paroxysmal torticollis of infancy is an unusual movement disorder, often accompanied by a family history of migraine. Some benign paroxysmal torticollis cases are associated with CACNA1A mutations. The authors sought to determine the frequency of CACNA1A mutations in benign paroxysmal torticollis by testing 8 children and their parents and by searching the literature for benign paroxysmal torticollis cases with accompanying CACNA1A mutations or other disorders linked to the same gene.

Familial transmission of 5p13.2 duplication due to maternal der(X)ins(X;5).

Submicroscopic duplications of 5p13 have been recently reported in several cases, warranting the description of a new clinical entity (Chromosome 5p13 Duplication Syndrome; MIM 613174). These microduplications, while variable in size, all contain at least part of the NIPBL gene. Patients with duplications in this region present with intellectual disability/developmental delay (ID/DD) and dysmorphic facies.

Biallelic mutations in huntington disease: A new case with just one affected parent, review of the literature and terminology.

Patients with biallelic mutations for Huntington disease (HD) are rare. We present a 46-year-old female with two expanded Huntingtin (HTT) alleles with just one known affected parent. This is the first reported patient with molecular studies performed to exclude HTT uniparental disomy (UPD).

Identification of Critical Region Responsible for Split Hand/Foot Malformation Type 3 (SHFM3) Phenotype through Systematic Review of Literature and Mapping of Breakpoints Using Microarray Data.

Split hand/foot malformation (SHFM) is a limb malformation with underdeveloped or absent central digital rays, clefts of hands and feet, and variable syndactyly of the remaining digits. There are six types of SHFM. Here, we report a boy with SHFM type 3 having normal 4th and 5th digits, absent 2nd and 3rd digits, and a 4th finger flexion deformity, as well as absent 2nd, 3rd and 4th toes bilaterally.

The syndrome of hypoparathyroidism, deafness, and renal anomalies.

Objective: We review the syndrome of hypoparathyroidism, deafness, and renal anomalies (HDR syndrome).

Methods: The current understanding and relevant literature pertaining to the background, genetic considerations, clinical features, prognosis, and treatment of HDR syndrome are reviewed.

Results: The combination of hypoparathyroidism, deafness, and renal anomalies constitutes an unusual syndrome associated most commonly with haploinsufficiency in GATA3, which encodes a transcription factor that binds to the (A/T) GATA (A/G) consensus DNA sequence.

Ataxia, dementia, and hypogonadotropism caused by disordered ubiquitination.

Background: The combination of ataxia and hypogonadism was first described more than a century ago, but its genetic basis has remained elusive.

Methods: We performed whole-exome sequencing in a patient with ataxia and hypogonadotropic hypogonadism, followed by targeted sequencing of candidate genes in similarly affected patients. Neurologic and reproductive endocrine phenotypes were characterized in detail.

Preserved proinsulin production in homozygous protein tyrosine phosphatase nonreceptor type 22 C1858T variant type 1 diabetes: a possible explanation for absence of overt ketoacidosis despite omission of exogenous insulin.

Objective: To report a postulated mechanism for resistance to overt ketoacidosis due to prolonged insulin omission in a severely hyperglycemic woman with a 14-year history of autoimmune type 1 diabetes (T1D).

Methods: History, physical examination, laboratory testing, and genotyping were performed. We also review the medical literature pertinent to this patient's phenotype and genotype.

Updates in the genetic evaluation of the child with global developmental delay or intellectual disability.

Global developmental delay (GDD) and intellectual disability (ID) occur in up to 3% of the general population and are even more commonly encountered in the setting of the pediatric neurology clinic. New advances in technology and in the understanding of genetic disorders have led to changes in the diagnostic approach to a child with unexplained GDD or ID. Chromosomal microarray has become a first-line test for evaluation of patients in this population and has both significantly increased diagnostic yield and introduced new challenges in the interpretation of copy number variants of uncertain significance.

Middle and inner ear malformations in mutation-proven branchio-oculo-facial (BOF) syndrome: case series and review of the literature.

Hearing impairment is common in individuals with branchio-oculo-facial (BOF) syndrome. The majority of described individuals have conductive hearing impairment due to malformed ossicles and/or external canal stenosis or atresia, although a sensorineural component to the hearing impairment in BOF syndrome is increasingly being reported. Sophisticated computed tomography (CT) of the temporal bone has revealed middle and inner ear malformations in three previous reports.

RASA1 analysis guides management in a family with capillary malformation-arteriovenous malformation.

Capillary malformation-arteriovenous malformation (CM-AVM; MIM 60354) is an autosomal dominant disorder characterized by multifocal cutaneous capillary malformations, often in association with fast-flow vascular lesions, which may be cutaneous, subcutaneous, intramuscular, intraosseus, or cerebral arteriovenous malformations or arteriovenous fistulas. CM-AVM results from heterozygous mutations in the RASA1 gene. Capillary malformations of the skin are common, and clinical examination alone may not be able to definitively diagnose-or exclude- CM-AVM.

A family with branchio-oculo-facial syndrome with primarily ocular involvement associated with mutation of the TFAP2A gene.

Background: Branchio-Oculo-Facial syndrome (BOFS) is a rare, autosomal dominant developmental disorder that has a distinct phenotype with characteristic craniofacial abnormalities. We report a family with extensive ocular manifestations of BOFS caused by a novel mutation in the transcription factor AP-2 alpha (TFAP2A) gene.

Materials And Methods: Case report of phenotypic and genotypic characterization of a family with BOFS.

Partial trisomy 8 mosaicism due to a pseudoisodicentric chromosome 8.

Chromosome 8 is the largest autosome in which mosaic trisomy is compatible with life. Constitutional trisomy 8 (T8) is estimated to occur in approximately 0.1% of all recognized pregnancies.