Robert William Marion

Genetic testing is becoming increasingly available for cardiac channelopathies, such as long QT syndrome and Brugada syndrome, which can lead to sudden cardiac death. Test results can be used to shape an individual’s medical management and to identify at-risk family members. In our qualitative study, all participants had a personal or family history of a diagnosed cardiac arrhythmia syndrome or sudden cardiac death. Open-ended interviews were conducted individually and in focus groups. ...

Opitz syndrome (OS) is an inherited disorder characterized by midline defects including hypertelorism, hypospadias, lip-palate-laryngotracheal clefts and imperforate anus. We have identified a new gene on Xp22f MIDI (Midline 1), which is disrupted in an OS patient carrying an X-chromosome inversion and is also mutated in several OS families. MID1 encodes a member of the B-box family of proteins, which contain protein–protein interaction domains, including a RING finger, and are ...

Hirschsprung disease is a developmental disorder resulting from the arrest of the craniocaudal migration of enteric neurons from the neural crest along gastrointestinal segments of variable length; see Behrman [Nelson textbook of pediatrics, 1992:954-956]. It is a heterogeneous disorder in which familial cases map to at least three loci whose function is necessary for normal neural crest-derived cell development. Homozygous mutations in the endothelin-B receptor gene (EDNRB) on 13q22 ...

Inherited cardiac arrhythmias such as long QT syndrome and Brugada syndrome, present clinical as well as ethical, legal, and social challenges. Many individuals who carry a deleterious mutation are largely asymptomatic and therefore may not be diagnosed until after the occurrence of a personal or family member's cardiac event. The familial nature of inherited genetic information raises numerous ethical, legal, and social issues regarding the sharing of genetic information, particularly ...

Interstitial deletions of 6q are associated with variable phenotypes, including growth retardation, dysmorphic features, upper limb malformations, and Prader–Willi (PW)-like features. Only a minority of cases in the literature have been characterized with high resolution techniques, making genotype–phenotype correlations difficult. We report 12 individuals with overlapping, 200-kb to 16.4-Mb interstitial deletions within 6q15q22.33 characterized by microarray-based comparative genomic ...

Tubulins, and microtubule polymers into which they incorporate, play critical mechanical roles in neuronal function during cell proliferation, neuronal migration, and postmigrational development: the three major overlapping events of mammalian cerebral cortex development. A number of neuronally expressed tubulin genes are associated with a spectrum of disorders affecting cerebral cortex formation. Such "tubulinopathies" include lissencephaly/pachygyria, polymicrogyria-like malformations, ...

Apert syndrome, an autosomal dominant disorder characterized by craniosynostosis, mid-facial malformations, symmetric bony syndactyly of hands and feet, and varying degrees of mental retardation, is most frequently caused by a de novo mutation. Two missense mutations in the fibroblast growth factor receptor 2 (FGFR2) gene have been found to account for the disorder in approximately 98% of affected patients. Seven cases of prenatal ultrasound diagnosis have been reported. Although one ...

Velocardiofacial syndrome (VCF) has overlapping features with DiGeorge sequence; both result from a developmental field defect and probably represent contiguous gene deletion syndromes. The association of chromosome 22q11 deletion with DiGeorge sequence led us to do molecular analysis of chromosome 22 in 18 patients with VCF, who ranged in age from 6 to 42 years. All 18 patients had monosomy for the chromosome region 22q11. Retrospectively, we correlated the presence of the deletion with ...

A series of earlier reports has described the velo-cardio-facial syndrome (VCFS), a syndrome of multiple anomalies including cleft palate, heart malformations, facial characteristics, and learning disabilities. The patients reported previously were primarily ascertained from a craniofacial program at a large tertiary medical center. Recent reports, including a companion paper in this issue, suggest that this common syndrome of clefting is also a common syndrome of congenital heart defect ...

We developed a bedside scoring system for diagnosis of trisomy 18 in the immediate neonatal period. Points are assigned for the presence of features known to occur in trisomy 18: five points for the presence of features previously reported in 50% or more of affected infants; three points for features reported to occur in between 10% and 50% of affected individuals; and one point for features known to occur in less than 10% of infants with the disorder. Using the scoring system, we ...

The combination of complex congenital heart disease (double outlet right ventricle with pulmonary atresia, malalignment ventriculoseptal defect, right-sided aortic arch with left ductus arteriosus) and bladder exstrophy occurred in an infant with Opitz syndrome. Neither of these defects has previously been reported in association with Opitz syndrome. These malformations, which are midline defects, further characterize this syndrome as an impairment in midline development. The spectrum of ...

We report a case of hepatoblastoma in a 10-year-old girl with mosaic-type trisomy 18. A comprehensive literature review reveals only 2 cases involving mosaic trisomy 18 patients. Our patient underwent an abbreviated chemotherapy course before complete surgical resection. Her hepatoblastoma did not contain cells with trisomy 18. The conservative management approach resulted in a successful outcome; she remains disease free >2 years after surgery. Along with presenting a literature review, ...

Presented are 2 patients with abnormal craniofacial region, limbs, and abdomen, features that may be consistent with Pfeiffer syndrome, type 3. Both patients had bicoronal and bisphenoidal synostosis, extreme exophthalmic midface hypoplasia, and hydrocephalus. The limbs had a fixed flexion deformity of the elbows with broad thumbs which were radiopalmarly deviated; the toes were broad with a varus deformity and syndactyly toes 2-5. Both patients developed bowel obstruction secondary to ...