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P J Goodfellow

Publications and source records attributed to P J Goodfellow.

At least 19 recordsLinked to original sources
PubMed1992

Isolation and high-resolution mapping of new DNA markers from the pericentromeric region of chromosome 10.

The gene responsible for multiple endocrine neoplasia type 2A (MEN 2A) has been localized to the pericentromeric region of chromosome 10. Several markers that fail to recombine with MEN2A have been identified, including D10Z1, D10S94, D10S97, and D10S102. Meiotic mapping in the MEN2A region is limited by the paucity of critical crossovers identified and by the dramatically reduced rates of recombination in males. Additional approaches to mapping loci in the pericentromeric region of chromosome 10 are required. We have undertaken the generation of a detailed physical map by radiation hybrid mapping. Here we report the development of a radiation hybrid panel and its use in the mapping of new DNA markers in pericentromeric chromosome 10. The radiation-reduced hybrids used for mapping studies all retain small subchromosomal fragments that include both D10S94 and D10Z1. One hybrid was selected as the source of DNA for cloning. One hundred five human recombinant clones were isolated from a lambda library made with pp11A DNA. We have completed regional mapping of 22 of those clones using our radiation hybrid mapping panel. Seven markers have been identified and, when taken together with previously meiotically mapped markers, define eight radiation hybrid map intervals between D10S34 and RBP3. The identical order is found for a number of these using either the radiation hybrid mapping panel or the meiotic mapping panel. We believe that this combination cloning and mapping approach will facilitate the precise positioning of new markers in pericentromeric chromosome 10 and will help in refining further the localization of MEN2A.

Centromere↗
PubMed1992

A high-resolution meiotic mapping panel for the pericentromeric region of chromosome 10.

Familial multiple endocrine neoplasia type 2A (MEN 2A) is a dominantly inherited cancer syndrome characterized by tumors in tissues derived from the neural crest. The disease manifests as medullary carcinoma of the thyroid, pheochromocytoma, and hyperparathyroidism. The MEN2A locus has been mapped near the centromere of chromosome 10 by linkage analysis. Statistical analyses have not resolved the location of MEN2A among several close markers. We have used our family material to refine the positions of 36 identified and confirmed crossovers among the markers most closely linked to MEN2A. This high-resolution meiotic mapping panel will help order loci in this pericentromeric region and narrow the region in which MEN2A maps.

Centromere↗
PubMed1992

A cluster of CpG islands at D10S94, near the locus responsible for multiple endocrine neoplasia type 2A (MEN2A).

We report the characterization of a dense cluster of CpG islands at D10S94 in proximal 10q11.2. D10S94 is tightly linked to the gene responsible for multiple endocrine neoplasia type 2A (MEN 2A), a dominantly inherited tumor syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytoma, and/or parathyroid adenoma. To date, no recombinants between D10S94 and MEN2A have been identified. The gene(s) responsible for two additional dominantly inherited disorders involving cancer of the medullary thyroid, MEN 2B (MEN2B), and dominantly inherited MTC without additional clinical features (MTC1), also map to this region. The gene or genes responsible for these disorders may be located at or near the D10S94 locus. A 570-kb long-range restriction map has been generated by pulsed-field gel electrophoresis using probes developed during a 160-kb bidirectional cosmid walk at D10S94. Six CpG islands are clustered within a 180-kb region; five fall within a 145-kb NotI restriction fragment that is contained in its entirety in our cosmid contig. The SacII, SfiI, and NotI restriction maps for lymphoblast and cloned DNA are concordant. These CpG islands may represent the 5' ends of candidate genes for MEN2A, MEN2B, and/or MTC1. One gene designated mcs94-1, which is associated with one of the CpG islands in this cluster, has been isolated and characterized in detail.

Base Sequence↗
PubMed1992

Identification and characterization of a gene at D10S94 in the MEN2A region.

We have identified a candidate for the gene responsible for multiple endocrine neoplasia type 2A (MEN 2A) at D10S94 in proximal 10q11.2. An evolutionarily conserved sequence from D10S94 was used as a probe to isolate cDNAs corresponding to a gene that we have termed mcs94-1. The gene spans 11 kb and has an unmethylated CpG island at its 5' end. The mcs94-1 transcript is approximately 2.4 kb in length and is widely expressed. It encodes a putative 415-amino-acid polypeptide that is similar in sequence to nucleolin, an abundant nucleolar protein. Mcs94-1 was examined as a candidate for MEN2A through nucleotide sequence analysis of mcs94-1 exons from an MEN 2A chromosome and its wildtype homologue from an MEN 2A patient. The major portion of the expressed mcs94-1 sequence was examined. No differences in sequence were found between the two alleles.

Amino Acid Sequence↗
PubMed1992

Human repeat element-mediated PCR: cloning and mapping of chromosome 10 DNA markers.

Repeat element-mediated PCR can facilitate rapid cloning and mapping of human chromosomal region-specific DNA markers from somatic cell hybrid DNA. PCR primers directed to human repeat elements result in human-specific DNA synthesis; template DNA derived from a somatic cell hybrid containing the human chromosomal region of interest provides region specificity. We have generated a series of repeat element-mediated PCR clones from a reduced complexity somatic cell hybrid containing a portion of human chromosome 10. The cloning source retains the centromere and tightly linked flanking markers, plus additional chromosome 10 sequences. Twelve new inter-Alu, two inter-L1, and four inter-Alu/L1 repeat element-mediated PCR clones were mapped by hybridization to Southern blots of repeat element-mediated PCR products amplified from somatic cell hybrid DNA templates. Two inter-Alu clones mapped to the pericentromeric region. We propose that a scarcity of Alu elements in the pericentromeric region of chromosome 10 contributed to the low number of clones obtained from this region. One inter-Alu clone, pC11/A1S-6-c23, defines the D10S94 locus, which is tightly linked to MEN2A and D10Z1.

Animals↗
PubMed1992

Genetic analysis of 24 French families with multiple endocrine neoplasia type 2A.

The gene for multiple endocrine neoplasia type 2A (MEN2A) has been mapped to the pericentromeric region of chromosome 10 by linkage analysis. Thirty-four families with multiple cases of medullary carcinoma of the thyroid (MTC), including 24 families with origins in France, have been typed with nine polymorphic markers spanning the centromere of chromosome 10. No recombination was observed between the MEN2A locus and either of the four loci D10Z1 (lod score 12.79), D10S102 (lod score 6.38), D10S94 (lod score 7.76), and D10S34 (lod score 5.94). There was no evidence for genetic linkage heterogeneity in the panel of 34 families. Haplotypes were constructed for a total of 11 polymorphisms in the MEN2A region, for mutation-bearing chromosomes in 24 French families and for 100 spouse controls. One haplotype was present in four MEN2A families but was not observed in any control (P less than .01). Two additional families share a core segment of this haplotype near the MEN2A gene. It is likely that these six families have a common affected ancestor. Because the incidence of pheochromocytoma among carriers varies from 0% to 74% within these six families, it is probable that additional factors modify the expression of the MEN2A gene.

Adrenal Gland Neoplasms↗
PubMed1992

Localization of the gene for MEN 2A.

The search for the gene that causes the multiple endocrine neoplasia type 2A (MEN 2A) syndrome is entering a new phase. Genetic linkage studies have localized the gene to the pericentromeric region of chromosome 10. The statistical portion of mapping the gene for MEN 2A is nearly complete and now classical molecular biological/gene mapping techniques will be employed. We have used fluorescence in situ hybridization to estimate the size of the MEN2A region to be about 2 to 5 mb, using some liberal assumptions; at worst the region should contain no more than about 10 mb of non-alphoid DNA. Our mapping panels (meiotic recombinant and radiation reduced hybrid) give consistent orders of markers in this small region. We describe our initial attempts to clone the region using yeast artificial chromosomes.

Chromosome Mapping↗
PubMed1992

A preliminary analysis of consortium data for markers tightly linked to multiple endocrine neoplasia type 2A.

We have analyzed DNA marker typing data contributed by six independent groups to estimate the pairwise genetic distances between these markers and the locus for multiple endocrine neoplasia type 2A (MEN 2A). We used LIPED to calculate these distances for female, male, and sex-average linkage maps and to determine the corresponding LOD scores. The preliminary analyses of this large data set (89 MEN 2A families and five non-MEN 2A references families, with 1,934 total individuals) are reported here. These refined estimates of the genetic map in this region will aid in the assignment of presymptomatic diagnoses. This study clearly points out the limitation of pairwise linkage analysis in further refining the position of MEN2A in this small region of chromosome 10. Further refinement of the genetic map position of MEN2A will be best accomplished by finding, verifying, and accurately mapping crossovers in specific families.

Chromosome Mapping↗
PubMed1992

Screening for multiple endocrine neoplasia type 2A with DNA-polymorphism analysis.

Nine chromosome 10 DNA markers (FNRB, D10S34, D10Z1, MEN203, D10S94, RBP3, D10S15, MBP [48.11], D10S22) were typed in two large Canadian pedigrees with multiple endocrine neoplasia type 2A (MEN 2A). These markers and the gene for MEN 2A (MEN2A) are believed to be in one linkage group spanning approximately 15 cM (male). MEN203 and D10S94 were informative and tightly linked to MEN2A with no recombinants observed in 26 meiotic events. D10S15 (MCK2), widely used in DNA genotyping predictions, demonstrated two recombinants in these two families. The use of multiple flanking markers increases both the likelihood of informativeness and the accuracy of risk assessments for predictive testing. We were able to assign a risk estimate for all 10 at-risk individuals.

Female↗
PubMed1992

Expression of the PAX2 gene in human fetal kidney and Wilms' tumor.

We have examined the pattern of expression of the human PAX2 gene in Wilms' tumors and human fetal kidney by Northern blot and in situ hybridization. Human PAX2 encodes a paired box-containing protein and has a high degree of homology with mouse and Drosophila paired box genes. In situ hybridization analysis reveals that PAX2 is expressed in nephrogenic structures in fetal kidney and also in Wilms' tumors. This pattern of expression suggests that PAX2 may have a role in differentiation of tissues in the kidney. In fetal kidney, PAX2 expression rapidly attenuates following the initial differentiation, but no evidence of attenuation was found in Wilms' tumors. The timing of PAX2 expression is restricted to fetal development, although high levels of expression were also observed in nephrogenic rests of residual normal juvenile kidney tissue adjacent to a Wilms' tumor. Nephrogenic rests are the presumptive precursors of Wilms' tumor but are not necessarily neoplastic. The failure of PAX2 expression to attenuate in Wilms' tumors and nephrogenic rests may be associated with events leading to the onset of Wilms' tumor. By somatic cell hybrid mapping, the PAX2 gene was localized to chromosome 10q22.1-q24.3, although this region has not previously been implicated in Wilms' tumor.

Amino Acid Sequence↗
PubMed1992

The gene responsible for X-linked cleft palate (CPX) in a British Columbia native kindred is localized between PGK1 and DXYS1.

Human craniofacial malformations are a class of common congenital anomalies in which the etiology is heterogeneous and often poorly understood. To better delineate the molecular basis of craniofacial development, we have undertaken a series of experiments directed toward the isolation of a gene involved in human secondary palate formation. DNA marker linkage studies have been performed in a large British Columbia (B.C.) Native family in which cleft palate segregates as an X-linked trait. We have examined 62 family members, including 15 affected males and 8 obligate carrier females. A previous clinical description of the clefting defect in this kindred included submucous cleft palate and bifid or absent uvula. Our recent reevaluation of the family has indicated that ankyloglossia (tongue-tie) is also a feature of X-linked cleft palate in some of the affected males and carrier females. Ankyloglossia has previously been associated with X-linked cleft palate in an Icelandic kindred in which a gene responsible for cleft palate (CPX) was assigned to the Xq21.3-q22 region between DXYS12 and DXS17. For the B.C. kindred reported here, we have mapped the gene responsible for cleft palate and/or ankyloglossia to a more proximal position on the X chromosome. No recombination was observed between B.C. CPX and the DNA marker DXS72 (peak lod score [Zmax] = 7.44 at recombination fraction [theta] = .0) localized to Xq21.1. Recombination was observed between CPX and PGK1 (Zmax = 7.35 at theta = .03) and between CPX and DXYS1 (Zmax = 5.59 at theta = .04). These recombination events localize B.C. CPX between PGK1 and DXYS1 in the Xq13-q21.31 region.

Blotting, Southern↗
PubMed1991

Intrachromosomal location of the telomeric repeat (TTAGGG)n.

Eukaryotic telomeres are specialized DNA-protein structures that are thought to ensure chromosomal stability and complete replication of the chromosome ends. All telomeres which have been studied consist of a tandem array of G-rich repeats which seem to be sufficient for telomere function. Originally, the human telomeric repeat (TTAGGG)n was assumed to be exclusively located at the very end of all human chromosomes. More recent evidence, however, suggests an extension into proterminal regions. Very little is known about the interstitial distribution of telomeric repeats. Here we present evidence for the presence of (TTAGGG)n repeats in internal loci on the long and short arms of different human chromosomes. In addition, we studied the genomic organization of these repeats in more detail and discuss possible functions of interstitial telomeric repeats in the human genome.

Base Sequence↗
PubMed1991

Regional assignment of the human uroporphyrinogen III synthase (UROS) gene to chromosome 10q25.2----q26.3.

Uroporphyrinogen III synthase [UROS; hydroxymethylbilane hydro-lyase (cyclizing), EC 4.2.1.75] is the fourth enzyme in the human heme biosynthetic pathway. The recent isolation of the cDNA encoding human UROS facilitated its chromosomal localization. Human UROS sequences were specifically amplified by the polymerase chain reaction (PCR) from genomic DNA of two independent panels of human-rodent somatic cell hybrids. There was 100% concordance for the presence of the human UROS PCR product and human chromosome 10. For each of the other chromosomes, there was 19%-53% discordance with human UROS. The chromosomal assignment was confirmed by Southern hybridization analysis of DNA from somatic cell hybrids with the full-length UROS cDNA. Using human-rodent hybrids containing different portions of human chromosome 10, we assigned the UROS gene to the region 10q25.2----q26.3.

Animals↗
PubMed1990

Generation of a panel of somatic cell hybrids containing unselected fragments of human chromosome 10 by X-ray irradiation and cell fusion: application to isolating the MEN2A region in hybrid cells.

We have used X-ray irradiation and cell fusion to generate somatic cell hybrids containing fragments of human chromosome 10. Our experiments were directed towards isolating the region of the MEN2A gene in hybrids and to use those as the source of DNA for cloning and mapping new markers from near the MEN2A locus. A number of hybrid clones containing human sequences that are tightly linked to the MEN2A gene were identified. Some 25% of our hybrids, however, proved to contain more than one human chromosome 10-derived fragment or showed evidence of deletions and/or rearrangements. A detailed analysis of the human content of X-ray irradiation hybrids is required to assess the integrity and number of human fragments retained. Despite retention of multiple human-derived fragments, these hybrids will prove useful as cloning and mapping resources.

Animals↗