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J R Yates

Publications and source records attributed to J R Yates.

At least 199 records · Page 11Linked to original sources
PubMed1987

Evidence that the gene for tuberous sclerosis is on chromosome 9.

Linkage analysis was undertaken in nineteen families with tuberous sclerosis by use of 26 polymorphic markers. All affected members fulfilled strict diagnostic criteria and unaffected members were rigorously investigated to confirm their status. Maximum lod scores were 1.20 for adenylate kinase 1 (AK1) at zero recombination and 3.85 for the ABO blood group at zero recombination (confidence limits 0-0.10). These findings support the assignment of the gene for tuberous sclerosis to the distal long arm of chromosome 9.

Adenylate Kinase↗
PubMed1987

A lethal multiple pterygium syndrome with apparent X-linked recessive inheritance.

We describe three male fetuses with a lethal multiple pterygium syndrome (LMPS). The family was ascertained when the first pregnancy of healthy, unrelated Scottish parents ended with a miscarriage at 23 weeks gestation. The macerated male fetus had a cystic hygroma, cleft palate, and webbing of the neck, elbows, and thighs. Radiographs showed lack of modeling of long bones, with broad ribs and clavicles, hypoplastic radii and ulnae, abnormal jaw angle, and dislocated femoral heads. Two other fetuses with similar anomalies were born to a first cousin of the propositus. These three male fetuses with a similar lethal multiple pterygium syndrome born to mothers who are second-degree relatives through the female line suggest X-linked recessive inheritance of LMPS in this family.

Abortion, Induced↗
PubMed1987

Multipoint linkage analysis of steroid sulfatase (X-linked ichthyosis) and distal Xp markers.

Six families with steroid sulfatase deficiency (STS; X-linked ichthyosis) have been studied with the Xg blood group (XG) and the DNA markers dic56 (DXS143), 782 (DXS85), pD2 (DXS43), and GMGX9. Carrier status of females was determined by assay of STS in hair roots. GMGX9 detects a frequent restriction fragment length polymorphism and also identifies a deletion in the majority of families with STS deficiency, including five of the six reported here. The linkage relationship of this marker to the others was studied in normal three-generation families yielding 32 phase-known meioses informative for two or more markers. No recombinants were observed between STS and GMGX9, giving a maximum lod score of 8.73 at zero recombination. Multipoint linkage analysis taking STS and GMGX9 as a single locus and incorporating two-point marker data and STS-XG data from published studies gave the map (Sequence: see text). This order was 2.4 times more likely than with (STS,GMGX9) and dic56 reversed and is supported by our findings in a male with steroid sulfatase deficiency due to a deletion of Xp22.3 which encompasses the XG locus. He is deleted for GMGX9 but shows normal hybridization to dic56 and 782.

Chromosome Mapping↗
PubMed1987

Is disordered folate metabolism the basis for the genetic predisposition to neural tube defects?

Vitamin levels were measured in twenty women under 35 years of age with a history of two or more neural tube defect pregnancies. Each index case was compared with a female control matched for age, obstetric history and social class. The mean concentration of red cell folate in the subjects was 178 ng/ml, significantly lower than the mean of 268 ng/ml for the control group (P = 0.005). Red cell folate levels showed a linear relationship with the number of neural tube defect pregnancies, the levels being lowest in women who had had three or four affected offspring. There was no significant difference in serum folate; plasma or white cell vitamin C; plasma vitamin A; thiamine, riboflavine or pyridoxine status; serum vitamin B12; plasma vitamin E; total protein, albumin, transferrin, magnesium, copper or zinc. Diet was assessed by a questionnaire. The dietary intakes of total folate and other vitamins except vitamin A were lower in the subjects than the controls but none of the differences were statistically significant. Regression analysis showed a difference between subjects and controls in the relationship of red cell folate to dietary folate. This study demonstrates an association between susceptibility to offspring with neural tube defects and depressed red cell folate levels which cannot be entirely attributed to a lower dietary intake of folate. It is postulated that one factor predisposing to the occurrence of neural tube defects may be an inherited disorder of folate metabolism.

Adult↗
PubMed1987

Two families of repeated DNA sequences in Thiobacillus ferrooxidans.

The genome of Thiobacillus ferrooxidans ATCC 19859 is about 2.8 X 10(6) base pairs as determined by analysis of reassociation kinetics of sheared DNA. This is 70% of the size of the genome of Escherichia coli. About 6% of the genome of T. ferrooxidans consists of moderately repetitive DNA sequences that are repeated an average of 20 times per genome. Two distinct repeated sequences, designated family 1 and family 2, have been analyzed in more detail. Both families are approximately 1 kilobase in length and are repeated 20 to 30 times per genome. Preliminary evidence from restriction enzyme analysis, Southern blotting experiments, and thermal melting analysis indicates that members of both families are conserved and are interspersed with single-copy DNA. Six copies of one family are present on the 45-kilobase-pair plasmid of strain ATCC 19859.

Chromosome Mapping↗
PubMed1987

Linkage analysis using multiple Xq DNA polymorphisms in normal families, families with the fragile X syndrome, and other families with X linked conditions.

Multipoint linkage analysis was undertaken with eight Xq cloned DNA sequences which identify one or more restriction fragment length polymorphisms in 26 families. These families comprise seven phase known normal families with three or more males in the third generation, seven families segregating for haemophilia B, one large family with dyskeratosis congenita, and 11 families with the fragile X syndrome. Phase known meioses informative for three or more loci supported the order centromere--DXYS1--DXS107--DXS102, DXS51--F9--FRAXA--DXS15, DXS52, F8--Xqter in each group of families studied. One of the normal families was segregating for protan colour blindness and showed a phase known recombination which would support the order centromere--F9--DXS52--CBP--Xqter. With the exception of DXYS1, all of these sequences have been localised to Xq27----qter by in situ hybridisation or hybridisation to Xq fragment panels, and on this basis should lie within 20 cM of one another. No recombination was observed between the sequences localised to Xq28, namely DXS52, F8, and DXS15 (between DXS15 and DXS52 Z = 12.25 at theta = 0 with confidence limits of 0 to 5 cM). However, an excess of recombination was apparent in the region of FRAXA with maximal lod scores as follows: F9 versus FRAXA (Z = 2.05, theta = 0.19), DXS52 versus FRAXA (Z = 1.85, theta = 0.26), and DXS15 versus FRAXA (Z = 1.33, theta = 0.27). No consistent differences were observed in the frequency of recombination when families with the fragile X syndrome were compared with normal families or families segregating for other X linked conditions. These results are compared with other published work and support the conclusion that although measurable linkage exists between these flanking markers and FRAXA, the intervals as measured by the frequency of meiotic recombination will seriously limit their clinical usefulness.

Chromosome Mapping↗
PubMed1987

Linkage of the tuberous sclerosis locus to a DNA polymorphism detected by v-abl.

Linkage analysis was undertaken in six families with tuberous sclerosis (TS) using a restriction fragment length polymorphism detected by v-abl. No recombinants were observed in 13 informative meioses (four phase known) giving a maximum lod score of 3.18 at zero recombination (confidence limits 0 to 0.15). This provides further evidence for the assignment of TS to 9q34 and should facilitate cloning of the structural gene, genetic counselling, and first trimester prenatal diagnosis.

DNA↗
PubMed1986

Protein sequencing by tandem mass spectrometry.

Methodology for determining amino acid sequences of proteins by tandem mass spectrometry is described. The approach involves enzymatic and/or chemical degradation of the protein to a collection of peptides which are then fractionated by high-performance liquid chromatography. Each fraction, containing as many as 10-15 peptides, is then analyzed directly, without further purification, by a combination of liquid secondary-ion/collision-activated dissociation mass spectrometry on a multianalyzer instrument. Interpretation of collision-activated dissociation mass spectra is described, and results are presented from a study of soluble peptides produced by treatment of apolipoprotein B with cyanogen bromide and trypsin.

Amino Acid Sequence↗
PubMed1986

Emery-Dreifuss muscular dystrophy: localisation to Xq27.3----qter confirmed by linkage to the factor VIII gene.

Two families with Emery-Dreifuss muscular dystrophy (EMD) have been studied with DNA markers mapping to Xq27.3----qter. No recombination was observed in 11 phase known meioses informative for the factor VIII gene (F8C) and eight phase known meioses informative for DXS15 (DX13), giving maximum lod scores of 3.50 and 2.50 respectively at a recombination fraction of zero. DXS52 (St14) showed one recombinant in 12 phase known meioses giving a maximum lod score of 2.62 at a recombination fraction of 0.07. These results map EMD to the distal end of the long arm of the X chromosome and are an important step in the development of tests for carrier detection and prenatal diagnosis.

Chromosome Mapping↗
PubMed1986

Genetic linkage.

Not all doctors would understand the statement "linkage is now established between a DNA marker and the locus for adult polycystic kidney disease at a recombination fraction of 5%". Yet over the next few years increasing numbers of DNA markers linked to single-gene disorders will become available and clinicians will need to identify patients who could benefit from this knowledge.

Blood Group Antigens↗
PubMed1986

Closed reduction of anterior subcoracoid shoulder dislocation. Evaluation of an external rotation method.

We prospectively evaluated an external rotation method for closed reduction of acute anterior shoulder dislocations that had been described recently. Seventy-eight of 100 consecutive emergency patients who presented with anterior shoulder dislocations experienced successful reduction using this external rotation method. The method proved to be easy to perform and relatively safe. Based on our findings, we recommend that it be included in the physician's armamentarium for initial closed reduction of anterior shoulder dislocation.

Adult↗
PubMed1985

Multipoint linkage analysis of the short arm of the human X chromosome in families with X-linked muscular dystrophy.

Sixteen three generation families from the West of Scotland with Duchenne muscular dystrophy (DMD) or Becker muscular dystrophy (BMD) have been studied using the Xg blood group and seven cloned DNA sequences which recognise DNA polymorphisms on the short arm of the X chromosome (Xp). Linkage has been established between DMD and probe 754 with a maximum lod score (Z) of 4.47 at a recombination fraction (theta) of 0.04. DMD has also been linked to probe 99-6 (Z = 3.75, theta = 0.03). Combining the data in this study with that of previously published work has established linkage between DMD and L1.28 (Z = 4.42, theta = 0.17) and altered the linkage estimate between BMD and L1.28 (Z = 3.50, theta = 0.22). An approximate order for the loci has been deduced by the study of recombinant chromosomes in phase known families informative for three or more loci. The proposed order is centromere--L1.28--754--DMD/BMD--99-6--D2--782--Xg. These results conclusively map both DMD and BMD to the central region of Xp and add weight to the original suggestion that they may be allelic.

Alleles↗
PubMed1985

A population study of adult onset limb-girdle muscular dystrophy.

Complete ascertainment of adult onset limb-girdle muscular dystrophy in the Lothian Region of Scotland was attempted. Ten index cases were identified giving a prevalence of 1.3 per 100 000 (0.9 per 100 000 for cases where the diagnosis of muscular dystrophy was supported by both electromyographic and muscle biopsy findings). In these 10 sibships there had been 11 affected subjects, significantly less than the 16.5 cases expected for autosomal recessive inheritance. Excluding cases suspected of being Becker muscular dystrophy, the prevalence was 0.7 per 100 000 (0.3 per 100 000 for proven cases of muscular dystrophy) and there remained a significant difference between the number of cases observed (5) and the number expected (9.1) for autosomal recessive inheritance. The prevalence of limb-girdle muscular dystrophy with onset in adult life has apparently declined over the past 30 years, as would be expected with the recognition of other conditions which cause the same pattern of weakness, making this a relatively rare disorder which should only be considered when other diagnoses have been excluded. The possibility that some cases diagnosed as limb-girdle muscular dystrophy may have had Becker muscular dystrophy emphasises the urgent need for a greater understanding of the biochemical basis of these conditions so that such diagnostic and genetic counselling dilemmas can be resolved.

Adolescent↗