Abstract A 10‐year follow‐up of a family with X‐linked cutaneous amyloidosis confirmed no more than streaks or spots of brown pigmentation of the skin in females but much more varied and severe manifestations in males. These included neonatal colitis, infantile diarrhea, recurrent respiratory infections, corneal dystrophy, photophobia, unruly hair with a frontal upsweep, dry skin, and mottled, muddy‐brown pigmentation seen first on the inner thighs and spreading diffusely to the buttocks, trunk, and arms. Amyloid was found in the pigmented skin of adults of both sexes but not in children. An autopsy of a 50‐year‐old man, subject to recurrent pneumonia, confirmed the presence of amyloid in the skin, but it was not found in other organs. Changes in the lungs were those of late‐stage diffuse pulmonary fibrosis. The pattern of inheritance is X‐linked, but the pathogenesis remains obscure.
Abstract Simulated data were generated under four etiologic mechanisms for each of 20 different pedigree structures drawn from a study of families ascertained through a proband with retinitis pigmentosa. These simulated data were then used to identify subgroups of pedigrees which best supported each of three genetic mechanisms (autosomal dominant, autosomal recessive, X‐linked recessive with 10% penetrance of disease in heterozygous females) and a non‐genetic, sporadic mechanism. Results of these studies show that pedigrees identified as supporting one genetic model in a “model choice” approach tend to be etiologically homogenous, but are not truly representative of all the phenotypic combinations possible under that mechanism. The problem of etiologic heterogeneity is most acute when dealing with pedigrees less than size 10. Pedigrees lumped under a non‐genetic, sporadic mechanism are extremely heterogeneous and studies of the natural history of diseases where both genetic and non‐genetic mechanisms may be operating (such as with retinitis pigmentosa) should avoid using this group of largely simplex pedigrees.
Abstract We have studied a 3‐month‐old boy with severe gastroesophageal reflux, feeding difficulties, neck and upper limb dystonia, abnormal ears, normal genitalia, and anatomically apparently normal larynx and trachea. Initially diagnosed as suffering from Sandifer “syndrome,” he was treated with a gastrostomy and Nissen fundoplication. However, his characteristic facial appearance subsequently led to the diagnosis of G syndrome.
The theory of the helical instability of the positive column has been generalized to include the case of a magnetic field with shear. The resultant stability criterion has been evaluated numerically. It predicts stabilization when the sense of the helical magnetic field opposes that of the helical density perturbation of the instability. This has been verified by an experiment in a hollow plasma column. The radial form of the density of the unperturbed plasma is required for the calculation and has been obtained by both theoretical and experimental methods.
Abstract Cerebral abnormalities are considered an obligatory manifestation of the Neu‐Laxova syndrome and include lissencephaly, severe microcephaly, aplasia of the corpus callosum, hypoplasia of the cerebellum, and other pathological changes. We present data on 3 cases with central nervous system anomalies, two of which have not been described previously, and summarize the literature on the subject. The problem of distinguishing type III lissencephaly is discussed.
Abstract We report on a patient with oculo‐dento‐osseous dysplasia and bilateral persistence of the hyaloid system. Autosomal recessive inheritance may be the cause of this patient's condition since she was born to unaffected first‐cousin parents. Ocular findings in the recessive variety of this syndrome seem to be more severe than those in the more common dominant form.
Abstract Recent advances in molecular biology provide measures of genotypes at loci involved in lipid metabolism. Genotypes for apolipoprotein E (apo E) and quantitative levels of total plasma cholesterol, betalipoprotein, and triglycerides were measured in a sample of 223 unrelated individuals from Nancy, France. The frequencies of the ε2, ε3, and ε4 alleles are 0.13, 0.74, and 0.13, respectively, in this sample. Significant differences among apo E genotypes were detected for these lipoprotein phenotypes. The average effect of the ε2 allele was to reduce total plasma cholesterol and betalipoprotein levels by 0.52 mmol/L and 0.98, respectively, while the ε4 allele raised these levels by 0.26 mmol/L and 0.61, respectively. Apo E genotype specific correlations suggest that this locus also has an effect on the coordinated metabolism between cholesterol and triglycerides. We infer that approximately 17% of the genetic variability in total plasma cholesterol may be attributable to this apo E polymorphism. No other single locus has been identified with such a large contribution to cardiovascular disease risk factors in the general population.
Abstract We report on a consanguineous Brazilian couple whose 2 children had tibial aplasia‐ectrodactyly. Femoral bifurcation was present in one of the affected children. The relationship of tibial aplasia‐ectrodactyly to the Gollop‐Wolfgang complex is discussed. Clinical and genetic aspects of the conditions involving tibial aplasia and femoral bifurcation are discussed.
Abstract We report on two brothers (in a sibship of three) with partial aniridia, cerebellar ataxia, and moderate mental retardation, with normal G‐banded chromosomes. Both present cerebellum hypoplasia; the younger also has congenital pulmonic stenosis. A review of the literature is presented. Cause is unknown, although the possibility of an autosomal recessive gene cannot be ruled out.
Abstract Our previous report demonstrated that two human cardiac α‐ and β‐myosin heavy‐chains (MHCs) which correspond to MYH6 and MYH7 respectively, according to Human Gene Mapping nomenclature, were mapped to human chromosome 14 and that human cardiac and skeletal MHC genes do not cosegregate. For further analysis, the regional mapping method was used. DNA from 4 human deletion and 3 human duplication cell lines were prepared for southern blotting, hybridized with human cardiac α‐ and β‐MHC DNA probes, and the hybridization intensity relative to 46,XX or 46,XY DNA was estimated. The results showed that two human cardiac MHC genes segregated with the 14cen→q13 region of the long arm of human chromosome 14. In situ hybridization of 3 H‐labeled human cardiac α‐MHC probe to normal human metaphase chromosome independently confirmed this result.
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