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Simon J Foote

Publications and source records attributed to Simon J Foote.

21 records · Page 2Linked to original sources

An ethyl-nitrosourea-induced point mutation in phex causes exon skipping, x-linked hypophosphatemia, and rickets.

We describe the clinical, genetic, biochemical, and molecular characterization of a mouse that arose in the first generation (G(1)) of a random mutagenesis screen with the chemical mutagen ethyl-nitrosourea. The mouse was observed to have skeletal abnormalities inherited with an X-linked dominant pattern of inheritance. The causative mutation, named Skeletal abnormality 1 (Ska1), was shown to be a single base pair mutation in a splice donor site immediately following exon 8 of the Phex (phosphate-regulating gene with homologies to endopeptidases located on the X-chromosome) gene. This point mutation caused skipping of exon 8 from Phex mRNA, hypophosphatemia, and features of rickets. This experimentally induced phenotype mirrors the human condition X-linked hypophosphatemia; directly confirms the role of Phex in phosphate homeostasis, normal skeletal development, and rickets; and illustrates the power of mutagenesis in exploring animal models of human disease.

Alleles↗

Mutation detection using mass spectrometric separation of tiny oligonucleotide fragments.

A DNA mutation detection protocol able to identify and characterize a previously unknown change in a given sequence in a rapid, efficient, sensitive, and inexpensive manner is required to take advantage of the resources now available to researchers through the genome sequencing projects. We have developed a method based on base-specific cleavage of polymerase chain reaction (PCR) products and then separation of the fragments by matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS), which can meet these criteria. Differences are seen as the presence, absence, or mass change of peaks corresponding to fragments affected by the base difference. This technique is shown through the detection of a polymorphism in the 3' untranslated region of IL12p40 from a double-stranded PCR product, and the detection of a single nucleotide polymorphism between two mouse strains. The sensitivity of the technique can be increased with the use of postsource decay, which enables differentiation of two fragments of identical mass but different sequence. The level of specificity and the rapid sample analysis time lend this technique to the mass screening of individuals for sequence changes and, in combination with MS sequencing methods, could be used to facilitate rapid resequencing of DNA.

3' Untranslated Regions↗

Mice that are congenic for the char2 locus are susceptible to malaria.

A major advance has been made towards the positional cloning of char2 (a quantitative trait locus encoding resistance to Plasmodium chabaudi malaria). Mice congenic for the locus have been used to fine map the gene and to prove that char2 plays a significant role in the outcome of malarial infection, independently of other resistance loci.

Animals↗