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C T Caskey

Publications and source records attributed to C T Caskey.

17 recordsLinked to original sources
PubMed1979

The HPRT locus.

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Amino Acid Sequence↗
PubMed1978

Detection of Fabry's disease heterozygotes by hair root analysis.

The alpha-galactosidase/beta-hexosaminidase ratio was measured for individual hair roots as a method for heterozygote detection in Fabry's disease. Hair root analysis in control individuals revealed no striking sex difference in alpha-galactosidase/beta-hexosaminidase ratio when five males and five females were compared. The values for the ratio X 100, calculating both enzyme activities in nmol of product per min per microliter of hair extract, ranged from 0.8 to 9 for controls and from less than 0.1 to 0.4 for two hemizygous males. Hair root analysis in four heterozygotes with clinical evidence of disease gave values for each individual in the control range, in the range for hemizygotes and in an intermediate range. The experience using hair root analysis for heterozygote detection in the X-linked Lesch-Nyhan syndrome suggests that this approch will be a sensitive heterozygote detection method which takes advantage of the occurrence of hairs with a deficient phenotype on the basis of Lyonization. We observed an affected male who was born to a female without clinical or biochemical evidence (examination included extensive hair root analysis) of Fabry's disease, thus documenting a likely instance of new mutation.

Adult↗
PubMed1978

An economic evaluation of a genetic screening program for Tay-Sachs disease.

The resolution of policy questions relating to medical genetic screening programs will not be without considerable difficulty. Examples include such issues as the optimal degree of screening program expansion, the relative values of screening for different genetic diseases, the appropriate sources of program funding (public vs. private), and the relative value of funding expanded genetic screening programs vs. research directed toward elimination of genetic traits themselves. Information on the net impact of the relevant alternatives is greatly needed, and this need will increase if the National Genetics Act receives funding approval. We have provided what is hopefully a contribution toward this end. While our analysis pertains to a specific disease and a specific screening program for that disease, the methodology is readily generalizable to other genetic diseases, as well as programs of any size or structure. Hopefully, this will serve to stimulate further research efforts that we believe are needed for the objective consideration of resource allocation alternatives.

Cost-Benefit Analysis↗
PubMed1977

Release factor binding to ribosome requires an intact 16 S rRNA 3' terminus.

Cloacin DF12 cleavage of Escherichia coli f[3H]MettRNA-AUG-ribosome complexes affects this substrate for in vitro peptide chain termination. Codon-directed release factors' (RF) 1 and 2 release of f[3H]methionine is inhibited by cloacin. Since cloacin inhibits RF1 and -2 binding to ribosomes but not RF-directed f[3H]methionine release from f[3H]met-tRNA-AUG-ribosome complexes when reactions contain 20% ethanol, we conclude that cloacin DF 13 inhibits formation of the termination codon recognition complex. Thus, cleavage of the 3'-OH 49-nucleotide sequence of the 16 S rRNA perturbs the codon-directed binding of RF to ribosomes.

Bacterial Proteins↗
PubMed1977

Mutations affecting the antigenic properties of hypoxanthine-guanine phosphoribosyl transferase in cultured Chinese hamster cells.

Cells of the mutant Chinese hamster strain RJK10 do not contain either hypoxanthine-guanine phosphoribosyl transferase activity (HGPRT) or protein that cross-reacts immunologically with HGPRT. HGPRT+ revertants have been isolated from RJK10 and those strains produce HGPRT with altered antigenic properties. HGPRT from the revertant cells is less reactive with anti-HGPRT serum than enzyme from the wild-type cells, and enzymes from the two sources are immunoprecipitated independently from mixtures of cell extracts. Thus one or more of the antigenic determinants present on Chinese hamster HGPRT are either missing or present in an altered form on HGPRT from revertants of RJK10. This indicates that RJK10 carries a mutation in the structural gene for HGPRT and that secondary mutations in the gene give rise to the revertants that produce the antigenically altered enzymes.

Cell Line↗
PubMed1976

Inherited biochemical defects affecting the kidney.

The identification of a disease entity as one that is the result of a heritable defect offers the physician an opportunity to intervene in a variety of ways. As emphasized, knowledge of the heritable pattern of a particular disease allows the physician an opportunity to counsel family members in personal disease risk and the offspring. Such genetic counseling results in a reduction of affected cases for many inherited diseases. There is every expectation that similar approaches would be effective for inherited renal diseases. The heritable diseases are a favored group for investigative purposes since these diseases result from a single gene defect no matter how plieotropic the effects of that defect. Thus the investigator is capable of constant probing with tools available for identifying that one event or component that lies at the basis of the disease. The emphasis of this chapter is on those inherited renal diseases for which we have reached a high level of understanding of this single defect. In many of these diseases a single enzyme is identified as deficient and is the presumed genetic defect. In others (cystinuria, RTA, and cystinosis) the precise biochemical answers appear close at hand. Thus a variety of therapeutic approaches to overcome either the gene defect or ill effects of the gene defect emerge for diseases involving the kidney and are listed in Table 7. For some of these diseases the new diagnostic technique of prenatal diagnosis can be used (Table 8). This genetic option provides couples at risk for bearing affected offspring with reduced risk. For a number of other diseases that are not identified by amniocentesis, this risk can be effectively lowered to acceptable levels by use of artificial insemination. Thus the inherited diseases of the kidney are amenable to medical intervention at a variety of levels. Such intervention can predictably lead to a lowering of both the incidence and consequences of these gene defects.

Acidosis, Renal Tubular↗
PubMed1975

Identifiying inherited disease through the family history.

The family pedigree record must be carefully recorded and reviewed on an annual basis. Review allows a continuting opportunity to identify new genetic risk factors. Physicians should be familiar with the pedigree patterns of autosomal dominant inheritance, sex-linked dominant inheritance, autosomal recessive inheritance, sex-linked recessive inheritance and polygenic inheritance. This understanding provides the basis for genetic counseling, prenatal diagnosis and improved therapy.

Adult↗
PubMedDate not supplied

Müllerian aplasia with hypoplastic thumbs: Two case reports.

Two cases of Müllerian aplasia associated with unilateral hypoplasia of the thumbs and skeletal spine deformities in two unrelated females are reported, and the pertinent literature is reviewed. Müllerian aplasia is frequently associated with skeletal spine deformities, but has not been reported to be associated with hypoplasia of the thumbs. Several heritable syndromes, including the hand-foot-uterus syndrome, are characterized by uterovaginal and distal extremity malformations but are not associated with skeletal spine anomalies. The two cases reported here represent a previously unreported constellation of anomalies.

Abnormalities, Multiple↗