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F Baas

Publications and source records attributed to F Baas.

116 records · Page 7Linked to original sources
PubMed1985

The human thyroglobulin gene: a polymorphic marker localized distal to C-MYC on chromosome 8 band q24.

The human thyroglobulin (Tg) gene is localized to chromosome 8 and regionally to band q24 as shown independently by both in situ hybridization techniques and Southern blot analysis of human-rodent somatic cell hybrids. Analysis of hybrids derived from a Burkitt lymphoma, with a translocation breakpoint in the oncogene c-myc, shows that the Tg gene is located distal from c-myc, towards the telomere of the long arm of chromosome 8. The finding of two high frequency restriction fragment length polymorphisms (RFLPs) in the 5' part of the Tg gene results in heterozygosity for at least one marker at chromosome 8, band q24, in 50% of a Caucasian population. These RFLPs cannot only be used for the study of inborn errors in Tg synthesis but also for linkage studies in the telomeric region of chromosome 8q.

Animals↗
PubMed1985

Photochemical reactions in interstellar grains photolysis of CO, NH3, and H2O.

A simulation of the organic layer accreted onto interstellar dust particles was prepared by slow deposition of a CO:NH2:H2O gas mixture on an Al block at 10 K, with concomitant irradiation with vacuum UV. The residues were analyzed by GC-MS, HPLC, and near IR; a reaction pathway leading from NH3 to complex alcohol, fatty acid, and amide products in 27 stages is postulated. The astronomical relevance and significance of the observations are discussed.

Ammonia↗
PubMed1984

Unusual scarcity of restriction site polymorphism in the human thyroglobulin gene. A linkage study suggesting autosomal dominance of a defective thyroglobulin allele.

Chromosomal DNA prepared from 90 unrelated individuals, mainly of Caucasian origin, was screened for restriction fragment length polymorphisms in the 3' 220 kilobase pairs (kb) of the human thyroglobulin (Tg) gene. The probes used were Tg cDNA fragments and subcloned single-copy genomic segments, isolated from a human cosmid library. All in all, 1164 nucleotides were screened using 15 different restriction enzymes. The average number of nucleotides screened was 354 per individual. Only one polymorphism was found in these 1164 nucleotides, with a minor allele frequency of 2.2%. This polymorphism, which is located in an intervening sequence, was found in healthy individuals and in a family with hereditary congenital hypothyroidism due to a defect in the synthesis and structure of thyroglobulin. The Mendelian segregation of polymorphism and goiter in ten family members suggests that the rare variant is linked to a normal Tg allele and provides strong evidence for autosomal dominant inheritance of this Tg synthesis defect.

Base Sequence↗
PubMed1983

The human thyroglobulin gene contains two 15-17 kb introns near its 3'-end.

We have cloned overlapping segments of the human thyroglobulin gene from a genomic cosmid library. Restriction mapping and electron microscopy show that a region of 38 kb at or near the 3'-end of this gene encodes only 850 nucleotides or 10% of the messenger RNA (mRNA) sequence. The region contains five exons of 130-210 nucleotides, split by introns of 1 to 15-17 kb. This represents the lowest ratio of coding to non-coding DNA (2.2%) found thus far in any eukaryotic gene. Blot hybridization under non-stringent conditions shows the presence of only one copy of this gene in the human genome and the absence of other closely related sequences.

Base Composition↗
PubMedDate not supplied

The gene for X-linked myotubular myopathy is located in an 8 Mb region at the border of Xq27.3 and Xq28.

X-linked recessive myotubular myopathy (XLMTM) is a rare and severe neonatal neuromuscular disease characterized by muscle weakness, hypotonia, and respiratory problems. Here we report an extensive linkage analysis in two families with XLMTM. Using 18 markers in the Xq27-Xqter region we found a maximum two-point lod score of Z = 4.00 at theta = 0.00 for the marker II-10 (DXS466). Three recombinations were detected between markers and the disease locus. At the distal side of Xq27.3 a recombination was present in between RNI (DXS369) and VK23b (DXS297), another in between VK23b (DXS297) and II-10 (DXS466), and at the proximal side of Xq28 a recombination in between U6.2 (DXS304) and Cpx67 (DXS134). Combining the results of both families we conclude that XLMTM is located in the 8 Mb(11 cM) region between VK23b (DXS297) and Cpx67 (DXS134).

Adult↗
PubMedDate not supplied

Chromosomal localization of a unique gene by non-autoradiographic in situ hybridization.

During the past few years, several methods have been developed for the detection of specific nucleic acid sequences by in situ hybridization using non-radioactive labels such as fluorochromes, cytochemically detectable enzymes and electron-dense markers. These methods are preferable to autoradiography in terms of speed of performance and topological resolution. Their limited sensitivity, however, has so far restricted their use to the detection of repeated sequences. Here we report single gene detection with a procedure using 2-acetylaminofluorene (AAF)-modified probes, immunoperoxidase cytochemistry and reflection-contrast microscopy. We confirmed the autoradiographic data on the localization of the human thyroglobulin (Tg) gene to the distal end of the long arm of chromosome 8. A mixture of cosmid cHT2-derived subclones of the 3' part of the Tg gene, 22.3 kilobase pairs (kbp) in total, was used as a hybridization probe. This procedure can be used to map other unique sequences, if genomic clones are available from which clones with an appropriate amount of inserts can be isolated.

2-Acetylaminofluorene↗
PubMedDate not supplied

Autosomal recessive inheritance of goiter in Dutch goats.

The inheritance of congenital goiter due to a thyroglobulin synthesis defect in a strain of Dutch goats has been studied by Mendelian and biochemical methods. Mendelian analysis of 301 matings, resulting in 591 kids, showed an autosomal recessive mode of inheritance. A restriction fragment length polymorphism (RFLP) in the thyroglobulin gene also was used to confirm the recessive mode of inheritance of the defect. In a pedigree consisting of 27 goats, spanning four generations, the genotype determined by RFLP study was in accordance with the observed phenotype and the autosomal inheritance of the defect. Although phenotypically no differences were detected between normal and heterozygous animals, the use of RFLPs allowed the diagnosis of the three genotypes.

Animals↗