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S J Jeremiah

Publications and source records attributed to S J Jeremiah.

18 recordsLinked to original sources
PubMed2005

Investigation of loss of heterozygosity and SNP frequencies in the RET gene in papillary thyroid carcinoma.

In both medullary carcinoma and papillary carcinoma of the thyroid, altered expression of the RET gene is implicated in tumorigenesis. Recent studies suggest that loss of heterozygosity (LOH) at the G691S SNP may be associated with tumors from patients with a history of radiation exposure. We investigated LOH for three RET SNPs (G691S, S904S, and L769L) in tumor and normal tissue from 46 patients from Ukraine and Belarus who were exposed to radioactive fallout following the Chernobyl nuclear accident and were operated for papillary thyroid carcinoma between 1995 and 2000. Normal tissue from 28 patients was heterozygous for at least one SNP; DNA from the corresponding tumor samples was also heterozygous, indicating that no LOH had taken place. To assess SNP frequencies in a radiation-associated thyroid cancer cohort, we investigated a further 68 unpaired post-Chernobyl samples. For G691S, there was considerable deviation from Hardy-Weinberg equilibrium; more detailed analysis showed that this was linked to age at onset of disease. Among younger patients, the distribution of genotypes conformed to Hardy-Weinberg equilibrium; among older patients, we observed marked deviation (p = 0.0072), with significant over-representation of the rare S allele relative to the younger groups (Fisher's exact, p = 0.0233). This suggests that SNPs in the RET oncogene may play a role in sporadic papillary thyroid carcinoma.

Adolescent↗
PubMed1998

A mutation screen of the TSC1 gene reveals 26 protein truncating mutations and 1 splice site mutation in a panel of 79 tuberous sclerosis patients.

The entire coding region of the TSC1 gene has been screened for mutations in 79 unrelated patients with tuberous sclerosis. Causative mutations have been found in 27 of these patients and five other variations in the gene have been identified. 26 of the mutations are predicted to cause premature truncation of the protein product of the gene and one mutation is in a splice site. The mutation screen has revealed that TSC1 mutations are rarer in sporadic tuberous sclerosis patients than in familial cases. We have also found that the only previously described case of non-penetrance can no longer be described as such, and that a single ungual fibroma is not necessarily diagnostic of tuberous sclerosis, important findings for the genetic counselling of tuberous sclerosis patients.

Blotting, Southern↗
PubMed1994

Chromosomal localization of human genes for arylamine N-acetyltransferase.

Arylamine N-acetyltransferase is encoded at two loci, AAC-1 and AAC-2, on human chromosome 8. The products of the two loci are able to catalyse N-acetylation of arylamine carcinogens, such as benzidine and other xenobiotics. AAC-2 is polymorphic and individuals carrying the slow-acetylator phenotype are more susceptible to benzidine-induced bladder cancer. We have identified yeast artificial chromosome clones encoding AAC-1 and AAC-2 and have used the cloned DNAs as fluorescent probes for in situ hybridization. The hybridization patterns allow assignment of AAC-1 and AAC-2 to chromosome 8p21.3-23.1, a region in which deletions have been associated with bladder cancer [Knowles, Shaw and Proctor (1993) Oncogene 8, 1357-1364].

Arylamine N-Acetyltransferase↗
PubMed1994

Two loci for tuberous sclerosis: one on 9q34 and one on 16p13.

32 families informative for the segregation of Tuberous sclerosis (TSC) have been examined for genetic markers on chromosomes 9, 11, 12 and 16. In one large family there was clear evidence of linkage to markers on chromosome 16p13.3 (lodscore with D16S291 of 4.7 at theta = 0) but other families were too small to give individually convincing lodscores. Combined results for all families gave positive results with ABO/DBH on chromosome 9 (max lod 2.63) and with D16S291 on chromosome 16 (max lod 3.98) at values of theta of 0.2 in each case. Further analysis showed strong evidence for heterogeneity with approximately half the families linked to a locus TSC1 on chromosome 9 between ASS and D9S298 and half to TSC2 on chromosome 16 close to D16S291. There was no definite support for a third locus although in many families this could not be excluded. In three families the segregation pattern of TSC remains unexplained. In two of these the family apparently segregates for TSC1 but in each case a single affected individual appeared to exclude the whole of the candidate region. Preliminary analysis of clinical features did not reveal any definite differences in incidence of mental handicap between individuals in different linkage groups or with different sex of the parent of origin. The frequencies of periungual fibromas and facial angiofibromas were also similar in both linkage groups. The difficulties of detecting linkage in small families where there is locus heterogeneity are discussed. The program ZZ was found to be helpful in this respect.

Adolescent↗
PubMed1990

Chromosomal mapping of a human phenol UDP-glucuronosyltransferase, GNT1.

A 5' fragment of a full-length cDNA clone encoding a human phenol UDP-glucuronosyltransferase was used to produce a specific probe for this gene. DNA isolated from a panel of 18 human-rodent somatic cell hybrids was analysed by Southern-blot hybridization. The results indicate that this UDP-glucuronosyltransferase is encoded by a single gene, designated GNT1, located on human chromosome 2.

Blotting, Southern↗
PubMed1990

The assignment of the genes coding for human complement components C6 and C7 to chromosome 5.

A panel of 19 somatic cell hybrids was tested for the presence of human sequences coding for complement components C6 and C7 by restriction enzyme digestion and Southern blots probed with human C6 and C7 cDNA probes. C7 was also detected by amplifying part of the human gene in hybrid DNA using the polymerase chain reaction. Detection of human C6 and C7 was completely correlated with the presence of chromosome 5.

Animals↗
PubMed1988

The assignment of the human gene coding for complement C5 to chromosome 9q22-9q33.

The presence or absence of the human gene for the fifth component of complement (C5) was analysed in 19 human-rodent hybrid cell lines by hybridization to a radiolabelled probe derived from a human C5 cDNA clone. The segregation of C5 in these hybrids suggested that the gene is localized on chromosome 9, in the region 9q21-9qter. In situ hybridization refined the assignment of C5 to chromosome 9q22-33.

Animals↗
PubMed1987

Studies of genetic linkage between adult polycystic kidney disease and three markers on chromosome 16.

Adult polycystic kidney disease (APKD) is a common genetic disorder that is inherited as an autosomal dominant trait. Recent reports show that, in some families, the APKD gene shows close genetic linkage to two chromosome 16 specific genetic markers. We have been conducting a genetic linkage study using 29 polymorphic isoenzyme and antigenic markers in 184 members of 12 APKD families. We present here the results of linkage analysis using three of these markers which have also been reported to be located on chromosome 16: phosphoglycolate phosphatase (PGP), glutamate pyruvate transaminase (GPT), and haptoglobin (HP). The results show that APKD is closely linked to the PGP locus on the short arm of chromosome 16 (16p13----p12), which is consistent with the previously reported linkage both to PGP and to the alpha globin locus. The genetic distance between PGP and APKD shows a maximum likelihood value of the recombination fraction at zero with a lod score of 5 X 5. There is no evidence of linkage between APKD and either GPT or HP. The PGP polymorphism potentially provides a useful predictive test to complement the use of alpha globin probes in genetic counselling. These tests should provide an efficient means of primary screening of family members at risk, as well as introducing the possibility of prenatal diagnosis.

Alanine Transaminase↗
PubMed1986

Two genetic markers closely linked to adult polycystic kidney disease on chromosome 16.

The genetic locus for autosomal dominant adult polycystic kidney disease was recently assigned to chromosome 16 by the finding of genetic linkage to the alpha globin gene cluster. Further study showed that the phosphoglycolate phosphatase locus is also closely linked to both the locus for adult polycystic kidney disease and the alpha globin gene cluster. These findings have important implications for the prenatal and presymptomatic diagnosis of adult polycystic kidney disease and for a better understanding of its pathogenesis.

Adolescent↗
PubMed1984

Complete hydatidiform moles combine maternal mitochondria with a paternal nuclear genome.

The parental origin of mitochondria in hydatidiform moles has been investigated by analysis of genetic variants of mtDNA restriction enzyme patterns. In six complete moles the mtDNA was found to be maternal in origin, with no contribution from the sperm mitochondria, while the nuclear genome was shown to be exclusively paternal in five cases. The occurrence of mtDNA variation in the healthy population was investigated using white blood cells and placentae, and the most common variation occurred at the Ava II restriction sites. The variants exhibited by molar mtDNA were the same as those found in material from healthy individuals.

DNA Restriction Enzymes↗
PubMed1982

Molecular size of enzymes in Trypanosoma cruzi considered in relationship to the genetic interpretation of isozyme patterns.

The molecular size of seven Trypanosoma cruzi enzymes, chosen because of their frequent use in studying trypanosome populations, has been found to be similar to that of their mammalian equivalents. Malic enzyme (NADP-dependent malate dehydrogenase, decarboxylating, EC 1.1.1.40) from T. cruzi has an apparent molecular size of only half that of the mammalian enzyme. The probable subunit structure of these T. cruzi enzymes has been deduced from the molecular weights by comparison with mammalian data. The results are compatible with recent interpretations of isozyme data implying the existence of genetic diploidy in trypanosomes.

Animals↗
PubMed1982

Mapping studies on human mitochondrial glutamate oxaloacetate transaminase.

Data from six primary hybrids and twenty-two subclones have confirmed the assignment of the mitochondrial form of glutamate oxaloacetate transaminase to chromosome 16. Family studies have provided independent confirmation of this and have suggested the gene order PGP-16qh-GOT2-HP. These studies were made easier by the development of a new stain for the detection of GOT activity.

Animals↗
PubMed1980

Assignment of the human locus determining phosphoglycolate phosphatase (PGP) to chromosome 16.

The segregation of human phosphoglycolate phosphatase has been studied in 52 independent human-rodent hybrids and 69 subclones. The results suggest that human PGP is on chromosome 16. Family data suggest that PGP is not close to 16qh or alpha Hp. The most likely regional assignment for PGP would appear to be 16p13 or 16p12, but a site on 16q cannot be entirely excluded. New data on 16qh and alpha Hp suggest that the male recombination fraction between these loci is about 0.2.

Alleles↗
PubMed1978

Further data on mitochondrial malic enzyme in man.

Mitochondrial malic enzyme was examined by starch-gel electrophoresis in human brain samples from 291 adults and 118 fetuses, all of European origin. Gene frequencies were estimated as MEM10.65 and MEM20.35. There was no significant difference in phenotype distribution between the sexes nor between adults and fetuses. No deviation from Hardy-Weinberg equilibrium was found. Malic enzyme was examined in various other tissues and although strongest in brain, it was also frequently active in adult testis, heart and kidney. An additional isozyme migrating less anodally than mitochondrial malic enzyme and especially prominent in heart muscle was found to be attributable to a combination of aconitase and isocitrate dehydrogenase acting on citrate in the gel buffer.

Adult↗