Search PubMed⌕ Search

Biomedical subjects

G N Wilson

Publications and source records attributed to G N Wilson.

At least 19 recordsLinked to original sources
PubMed1996

Robertsonian (15q;15q) translocation in a child with Angelman syndrome: evidence of uniparental disomy.

A balanced Robertsonian translocation 45,XY,t(15q15q) was detected in a patient with mental retardation, microcephaly, and hypertonia. Deletion of the 15q11q13 region was unlikely based on fluorescence in situ hybridization studies that revealed hybridization of appropriate DNA probes to both arms of the Robertsonian chromosome. Inheritance of alleles from 13 highly polymorphic DNA markers on chromosome 15 showed paternal uniparental isodisomy. The clinical, cytogenetic, and molecular results are consistent with a diagnosis of Angelman syndrome.

Angelman Syndrome↗
PubMed1996

Is there a cocaine syndrome? Dysmorphic and anthropometric assessment of infants exposed to cocaine.

It was suggested that a "fetal cocaine syndrome" exists. The objective of this study was to systematically investigate whether or not a "cocaine syndrome" exists. The setting was Parkland Memorial Hospital, a large urban public hospital in Dallas, TX, where approximately 15,000 infants are delivered annually. Infants who tested positive by urinalysis for cocaine (n = 25) were included in this study. Controls negative for cocaine (n = 25) were matched to cocaine-exposed infants for estimated gestational age, sex, and race. A standardized dysmorphology examination (135 features) and a series of anthropometric measures (n = 22) were done for each cocaine-exposed and control infant by an observer blinded to drug-exposure status. Fetal growth retardation characterized cocaine-exposed infants. No characteristic pattern of minor dysmorphic or anthropometric features of the face, limbs, or torso was observed among cocaine-exposed infants. Cocaine-exposed infants lack a facial gestalt or torso/limb features that would characterize a syndrome. If a "cocaine syndrome" that can be characterized dysmorphologically and/or anthropometrically exists, its occurrence seems infrequent.

Abnormalities, Drug-Induced↗
PubMed1995

Interstitial deletions 4q21.1q25 and 4q25q27: phenotypic variability and relation to Rieger anomaly.

We describe clinical and chromosomal findings in two patients with del(4q). Patient 1, with interstitial deletion (4)(q21.1q25), had craniofacial and skeletal anomalies and died at 8 months of hydrocephalus. Patient 2, with interstitial deletion (4)(q25q27), had craniofacial and skeletal anomalies with congenital hypotonia and developmental delay. These patients shared certain manifestations with other del(4q) patients but did not have Rieger anomaly. Clinical variability among patients with interstitial deletions of 4q may be related to variable expression, variable deletion, or imprinting of genes within the 4q region.

Abnormalities, Multiple↗
PubMed1995

Differential evolution and expression of murine peroxisomal membrane protein genes.

Gene segments encoding the 70 and 22-kDa peroxisomal membrane proteins (PMP) have been characterized in mice and compared with other peroxisomal proteins in terms of evolution and expression. The mouse PMP22 gene sequence predicts A16G and I136V substitutions that agree with those defined by cyanogen bromide cleavage analysis, providing additional evidence that this gene encodes the major 22-kDa membrane protein visualized by SDS-polyacrylamide electrophoresis. Mammalian PMP22 genes exhibit high evolutionary rates (0.17% amino acid substitution per million years) than PMP35 (0.14%), PMP70 (0.07%), or catalase genes (0.13%). PMP70 gene regions are conserved throughout vertebrate phylas based on Southern analysis, while PMP22 sequences were only detected in rodents. Amino acid substitutions are clustered in both PMP22 and PMP70 genes, and their pattern supports membrane topologies derived from hydropathy profiles. Northern blot analysis identifies single mRNAs of 4.6 kb (PMP70), 1.4 kb (PMP22), and 2.3 kb (catalase) in several rodent tissues. Quantitative or competitive RT-PCR assays detected two- to three-fold greater numbers of catalase mRNA molecules relative to PMP mRNA molecules in brain, liver, and kidney; PMP22 and PMP35 mRNAs were two-fold more abundant than PMP70 mRNA in these tissues. Steady-state levels of PMP22 mRNA were highest in rodent liver kidney, spinal cord, and duodenum with low levels in colon, adrenal, thymus, and spleen. We conclude that PMP genes exhibit independent evolutionary rates and tissue regulation, suggesting that they have unique roles in peroxisome biogenesis and tissue differentiation.

ATP-Binding Cassette Transporters↗
PubMed1994

Structure and expression of mammalian peroxisome assembly factor-1 (PMP35) genes.

Mammalian genes encoding a 35-kDa peroxisomal membrane protein (PMP35, peroxisome assembly factor-1) are compared using the polymerase chain reaction and DNA sequencing. DNA sequencing of the 915 bp of the PMP35 coding regions was in complete agreement with previously published rat data and showed 36 and 133 nucleotide substitutions, respectively, in mouse and man. The 12 and 35 respective amino acid changes encoded by these nucleotide substitutions are clustered and compatible with putative membrane-spanning regions. Rat/human and rat/mouse comparisons yield silent mutation rates of 0.33 and 0.21% per site per million years and replacement mutation rates of 0.082 and 0.076%; transitions account for 67% (human/mouse) and 83% (rat/mouse) of nucleotide replacements among PMP35 genes. PMP35 gene expression in mouse tissues as measured by reverse transcriptase-PCR was responsive to clofibrate and disproportionately high in neural tissue.

Amino Acid Sequence↗
PubMed1994

Multiple coagulation defects and the Cohen syndrome.

A 13-year-old male presented with new onset seizures, sagittal sinus thrombosis with cerebral hemorrhage, and extensive venous thrombosis of the lower limbs. Laboratory investigation demonstrated combined deficiency of protein C, protein S, and antithrombin III. He and his 17-year-old sister had a mental retardation-multiple anomaly syndrome associated with microcephaly, unusual facies, and lax connective tissue. Their dysmorphology included elongated faces with narrow forehead, arched eyebrows, large mouth with down-turned corners, malformed teeth, and furrowed tongue. Both had Marfanoid habitus with lax joints, pectus excavatum, kyphoscoliosis, and flat narrow feet. The most likely diagnosis for these siblings is the autosomal recessive Cohen syndrome of mental retardation, congenital hypotonia with Marfanoid habitus, microcephaly, pleasant affect, micrognathia, and open mouth with prominent incisors. The sagittal sinus thrombosis, left frontal intracranial hemorrhage, carotid aneurysm, tortuous descending aorta, and deep venous thrombosis suffered by the male sibling adds the Cohen syndrome to genetic vasculopathies that may be associated with stroke.

Adolescent↗
PubMed1994

Atypical inheritance: new horizons for neurology.

Rediscovery of Mendel's laws produced an enthusiastic new discipline at the turn of this century. The eugenics movement had many disciples in the United States, and it should be noted that the term "final solution" was first used by the National Association of Charities and Corrections in the 1920s. American advocates of eugenics accomplished mass sterilization of retarded individuals and the prohibition of Jewish immigration from Germany during World War II. It is interesting that the close of this century has produced a similar revolution in genetics. These newer genetic mechanisms expose the major fallacy of eugenics: traits may be genetic without showing obvious familial transmission. Sanctions against reproduction or immigration thus will have little effect on the gene pool. The clinical implications of atypical inheritance are enormous. Almost every medical disorder must be reinvestigated for evidence of subtle chromosome changes, for worsening in progressive generations, and for influence of parental origin. The classical Mendelian model taught that extreme and rare phenotypes shed light on more frequent ones, hence the definition of genes responsible for hypercholesterolemia, for Alzheimer disease, and for amyotrophic lateral sclerosis. Atypical inheritance mechanisms further enhance this approach, bringing all of neurology under the light of genetic technology. The lure for the practitioner, then, is not the hyperbole of molecular biology; it is the need for a seasoned hand so emphasized by Huntington's disease and the duty to protect the next century from disasters of the current one.

Animals↗
PubMed1993

Three cases of dup(10p)/del(10q) syndrome resulting from maternal pericentric inversion.

Two families and 3 patients with dup(10p)/del(10q) syndrome segregating from a maternal pericentric inversion are described, including a stillborn female with Potter sequence and multicystic renal dysplasia. Comparison of 32 dup(10p) patients to 11 del(10)(q25) patients emphasized dolichocephaly, wide sutures, frontal bossing, micrognathia, and renal defects as distinguishing characteristics of the dup(10p) syndrome. The 3 new and 6 previously reported dup(10p)/del(10q) patients had several manifestations in common with the dup(10p) and del(10q) syndromes, but were more typical of dup(10p) syndrome with respect to all 5 distinguishing characters.

Abnormalities, Multiple↗
PubMed1993

Genomic imprinting: summary of an NICHD conference.

Compelling evidence for genomic imprinting as a pathogenetic mechanism in humans mandates re-evaluation of every genetic or multifactorial disease for parent-of-origin effects. In an expanding list of malformation syndromes, cancers, growth abnormalities, and chromosomal disorders, phenotypes may be determined by source rather than content of transmitted DNA. A multidisciplinary conference held on April 13-14, 1992, reviewed the substantial impact of genomic imprinting in mouse development and discussed in role in human pregnancy, childhood cancers, chromosomal translocations, X-inactivation, and several disorders associated with mental retardation. Topics for future research include the mechanism, timing, reversibility, and homology of the imprinting process.

Animals↗
PubMed1993

Index finger hyperphalangy and multiple anomalies: Catel-Manzke syndrome?

We describe a boy with short stature, developmental delay, unusual face, right iris coloboma, malformed ears, micrognathia, and skeletal anomalies including hyperphalangy of the index fingers, bilateral fifth finger clinodactyly, short halluces, and scoliosis. Internal anomalies included asymmetric and dilated cerebral ventricles and ventricular septal defect. The neonatal history of small jaw with feeding and respiratory difficulties suggested a Pierre Robin sequence, but there was no cleft palate. Two maternal uncles with similar anomalies had died at ages 13 months and 5 years, respectively. RFLP studies with the DNA probes DXS72 and F8C were consistent with but not diagnostic of X-linked recessive inheritance. The pattern of anomalies was compatible with a diagnosis of Catel-Manzke syndrome, but a novel dysostosis syndrome must also be considered.

Abnormalities, Multiple↗
PubMed1992

Genomics of human dysmorphogenesis.

A survey of Mendelian Inheritance in Man emphasizes the large Mendelian contribution to human dysmorphogenesis and contrasts single gene conditions with chromosomal disorders. There were 1761 conditions that involved altered morphogenesis (49% of disease entries), including 1040 multiple defect syndromes and 721 inherited single birth defects. Premature death (36-57%), mental retardation (20-59%), and growth retardation (37-59%) are more frequent in autosomal recessive or X-linked syndromes, while predisposition to tumorigenesis was more common in dominant (16%) than recessive (3.4%) syndromes. Comparison of the Mendelian conditions with 100 chromosomal disorders showed a strikingly similar spectrum of malformation, with skeletal, craniofacial, eye, epidermal, and neuromuscular systems being most frequently affected. Chromosomal syndromes average 10.6 systems affected per disorder, in contrast to 3.55 for Mendelian syndromes, and pleiotropy does correlate weakly with aneuploid segment length. Genomic understanding of these relationships is still primitive, with 74 of 1609 (4.6%) autosomal conditions and 43 of 152 (29%) X-linked conditions mapped to specific chromosomal regions. The societal toll of human dysmorphogenesis and the evident progress with X-linked disorders provide a powerful rationale for the Human Genome Project.

Chromosome Aberrations↗
PubMed1992

Dietary ether lipid incorporation into tissue plasmalogens of humans and rodents.

Chronic feeding of 1-O-octadecyl-sn-glycerol (batyl alcohol) to patients suffering from congenital deficiency in tissue ether glycerolipids showed an increase in the plasmalogens content of their erythrocytes. However, nothing is known about the ether lipid content of other tissues in these patients. Feeding 1-O-heptadecyl-sn-glycerol to young rats showed that this uncommon ether lipid was incorporated to a high extent into the plasmalogens of all tissues except brain. Comparative studies with other precursors, such as 3-O-heptadecyl-sn-glycerol, heptadecanol and heptadecanoic acid, indicated a stereospecific incorporation of the dietary 1-O-alkyl-sn-glycerols into tissue plasmalogens without cleavage of the ether bond. Dietary ether lipids were also shown to be transferred from mothers to suckling rats, but not from pregnant rats to fetuses. The implication of these results to possible dietary ether lipid therapy for patients suffering from peroxisomal disorders is discussed.

Acyltransferases↗
PubMed1992

Mutational risks in females: genomic imprinting and maternal molecules.

Genetic mechanisms for selective mutagenesis in female mammals might include alterations of genomic imprinting, maternally derived molecules, mitochondrial DNA or sex chromosome loci. None of these mechanisms provides an obvious explanation for the higher mutational rates observed for certain mutagens in mouse female pronuclei, but the association of DNA methylation with maternal genomic imprinting is an enticing avenue for research. Further characterization of the extent and homology of genomic imprinting among mammals is required before its relevance to mutagenesis can be determined. The existence of maternal effect mutations in mammals merits evaluation but is not yet proven. The relevance of mitochondrial DNA to female-specific mutagenesis will be greatest in multi-generational studies.

Animals↗
PubMed1992

Non-specific X linked mental retardation with aphasia exhibiting genetic linkage to chromosomal region Xp11.

A new type of non-specific X linked mental retardation is described in a three generation family. The three affected males had severe mental retardation (IQ 20 to 30), mutism, growth failure, frequent infections, seizures, and the following minor anomalies: brachycephaly, frontal hair whorl, square face, large mouth, thick lips, and prognathism. There was not a characteristic facies. Normal laboratory studies on the proband included a karyotype with fragile X screening, skeletal survey, blood amino acid, urine organic acid, and HGPRT levels. Linkage analysis was performed with 10 X chromosome DNA probes of which probe DXS255 at chromosomal region Xp11.22 gave a maximal two point lod score of 2.10 if phase was inferred and 1.20 if it was not. Crossovers were shown with probes mapping to regions Xp22, Xp21, and Xq28. Comparison of these patients with 80 X linked causes of mental retardation, including 41 which might be classified as 'non-specific', showed no other disorders compatible with the phenotypic and linkage data.

Abnormalities, Multiple↗
PubMed1992

Human congenital anomalies: application of new genetic tools and concepts.

The discovery of nontraditional inheritance and of developmental gene families common to all metazoans has revolutionized research on human congenital anomalies. The most gratifying results of these new concepts are summarized in Table 5: several human syndromes have already been related to their causative genes. Classic embryonic mechanisms (ie, gastrulation, segmentation, adhesion) also have been correlated with specific molecules. Perhaps most optimistic are the facts that many of the relevant molecules can be viewed as growth factors and that many anomalies are examples of extended or arrested development known as heterochrony. The implication is that genetic screening and preconceptional diagnosis will allow treatment of congenital malformations by supplementation/suppression of the maternofetal unit. This future specialty of "gestational endocrinology" is already being used for embryonic therapy of 21-hydroxylase deficiency.

Alleles↗
PubMed1991

Keratitis, hepatitis, ichthyosis, and deafness: report and review of KID syndrome.

A 14-year-old girl with ichthyosis and severe liver disease is compared to 35 reported cases of KID or Senter syndrome. Common manifestations such as ichthyosis (35/35 patients), sensorineural deafness (33/34), "ectodermal dysplasia" (25/28), corneal abnormality (26/31) were present in the proposita, while less common manifestations such as chronic infections (15/20) and neuromuscular disease (12/35) were absent. Two families with vertical transmission and 28 sporadic cases are compatible with an autosomal dominant form of KID syndrome, while one inbred sibship with liver disease suggests the existence of an autosomal recessive form. The proposita was similar to the latter patients in having progressive cirrhosis necessitating liver transplantation; she also had short stature (10/35 patients) and mental retardation (3/35). Hepatic findings included micronodular cirrhosis, cholestasis, hyperplastic Kupffer cells, abundant Mallory's hyaline, copper accumulation without steatosis, and normal peroxisomes.

Adolescent↗