Abstract
We have identified 14 families with ataxia-telangiectasia (A-T) in which mutation of the ATM gene is associated with a less severe clinical and cellular phenotype (approximately 10%-15% of A-T families identified in the United Kingdom). In 10 of these families, all the homozygotes have a 137-bp insertion in their cDNA caused by a point mutation in a sequence resembling a splice-donor site. The second A-T allele has a different mutation in each patient. We show that the less severe phenotype in these patients is caused by some degree of normal splicing, which occurs as an alternative product from the insertion-containing allele. The level of the 137-bp PCR product containing the insertion was lowest in two patients who showed a later onset of cerebellar ataxia. A further four families who do not have this insertion have been identified. Mutations detected in two of four of these are missense mutations, normally rare in A-T patients. The demonstration of mutations giving rise to a slightly milder phenotype in A-T raises the interesting question of what range of phenotypes might occur in individuals in whom both mutations are milder. One possibility might be that individuals who are compound heterozygotes for ATM mutations are more common than we realize.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Brown E. J., Albers M. W., Shin T. B., Ichikawa K., Keith C. T., Lane W. S., Schreiber S. L. A mammalian protein targeted by G1-arresting rapamycin-receptor complex. Nature. 1994 Jun 30;369(6483):756–758. doi: 10.1038/369756a0. [DOI] [PubMed] [Google Scholar]
- Byrd P. J., McConville C. M., Cooper P., Parkhill J., Stankovic T., McGuire G. M., Thick J. A., Taylor A. M. Mutations revealed by sequencing the 5' half of the gene for ataxia telangiectasia. Hum Mol Genet. 1996 Jan;5(1):145–149. doi: 10.1093/hmg/5.1.145. [DOI] [PubMed] [Google Scholar]
- Gilad S., Khosravi R., Shkedy D., Uziel T., Ziv Y., Savitsky K., Rotman G., Smith S., Chessa L., Jorgensen T. J. Predominance of null mutations in ataxia-telangiectasia. Hum Mol Genet. 1996 Apr;5(4):433–439. doi: 10.1093/hmg/5.4.433. [DOI] [PubMed] [Google Scholar]
- Hari K. L., Santerre A., Sekelsky J. J., McKim K. S., Boyd J. B., Hawley R. S. The mei-41 gene of D. melanogaster is a structural and functional homolog of the human ataxia telangiectasia gene. Cell. 1995 Sep 8;82(5):815–821. doi: 10.1016/0092-8674(95)90478-6. [DOI] [PubMed] [Google Scholar]
- Hollmann M., Boulter J., Maron C., Beasley L., Sullivan J., Pecht G., Heinemann S. Zinc potentiates agonist-induced currents at certain splice variants of the NMDA receptor. Neuron. 1993 May;10(5):943–954. doi: 10.1016/0896-6273(93)90209-a. [DOI] [PubMed] [Google Scholar]
- Jimenez G., Yucel J., Rowley R., Subramani S. The rad3+ gene of Schizosaccharomyces pombe is involved in multiple checkpoint functions and in DNA repair. Proc Natl Acad Sci U S A. 1992 Jun 1;89(11):4952–4956. doi: 10.1073/pnas.89.11.4952. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lelli N., Garuti R., Ghisellini M., Tiozzo R., Rolleri M., Aimale V., Ginocchio E., Naselli A., Bertolini S., Calandra S. Occurrence of multiple aberrantly spliced mRNAs of the LDL-receptor gene upon a donor splice site mutation that causes familial hypercholesterolemia (FHBenevento). J Lipid Res. 1995 Jun;36(6):1315–1324. [PubMed] [Google Scholar]
- Liu Q., Sommer S. S. Restriction endonuclease fingerprinting (REF): a sensitive method for screening mutations in long, contiguous segments of DNA. Biotechniques. 1995 Mar;18(3):470–477. [PubMed] [Google Scholar]
- McConville C. M., Byrd P. J., Ambrose H. J., Taylor A. M. Genetic and physical mapping of the ataxia-telangiectasia locus on chromosome 11q22-q23. Int J Radiat Biol. 1994 Dec;66(6 Suppl):S45–S56. [PubMed] [Google Scholar]
- Sabatini D. M., Erdjument-Bromage H., Lui M., Tempst P., Snyder S. H. RAFT1: a mammalian protein that binds to FKBP12 in a rapamycin-dependent fashion and is homologous to yeast TORs. Cell. 1994 Jul 15;78(1):35–43. doi: 10.1016/0092-8674(94)90570-3. [DOI] [PubMed] [Google Scholar]
- Savitsky K., Bar-Shira A., Gilad S., Rotman G., Ziv Y., Vanagaite L., Tagle D. A., Smith S., Uziel T., Sfez S. A single ataxia telangiectasia gene with a product similar to PI-3 kinase. Science. 1995 Jun 23;268(5218):1749–1753. doi: 10.1126/science.7792600. [DOI] [PubMed] [Google Scholar]
- Savitsky K., Sfez S., Tagle D. A., Ziv Y., Sartiel A., Collins F. S., Shiloh Y., Rotman G. The complete sequence of the coding region of the ATM gene reveals similarity to cell cycle regulators in different species. Hum Mol Genet. 1995 Nov;4(11):2025–2032. doi: 10.1093/hmg/4.11.2025. [DOI] [PubMed] [Google Scholar]
- Seaton B. L., Yucel J., Sunnerhagen P., Subramani S. Isolation and characterization of the Schizosaccharomyces pombe rad3 gene, involved in the DNA damage and DNA synthesis checkpoints. Gene. 1992 Sep 21;119(1):83–89. doi: 10.1016/0378-1119(92)90069-2. [DOI] [PubMed] [Google Scholar]
- Shapiro M. B., Senapathy P. RNA splice junctions of different classes of eukaryotes: sequence statistics and functional implications in gene expression. Nucleic Acids Res. 1987 Sep 11;15(17):7155–7174. doi: 10.1093/nar/15.17.7155. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stamm S., Zhang M. Q., Marr T. G., Helfman D. M. A sequence compilation and comparison of exons that are alternatively spliced in neurons. Nucleic Acids Res. 1994 May 11;22(9):1515–1526. doi: 10.1093/nar/22.9.1515. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Szabo C. I., King M. C. Inherited breast and ovarian cancer. Hum Mol Genet. 1995;4(Spec No):1811–1817. doi: 10.1093/hmg/4.suppl_1.1811. [DOI] [PubMed] [Google Scholar]
- Taylor A. M., McConville C. M., Rotman G., Shiloh Y., Byrd P. J. A haplotype common to intermediate radiosensitivity variants of ataxia-telangiectasia in the UK. Int J Radiat Biol. 1994 Dec;66(6 Suppl):S35–S41. [PubMed] [Google Scholar]
- Taylor A. M., Metcalfe J. A., Thick J., Mak Y. F. Leukemia and lymphoma in ataxia telangiectasia. Blood. 1996 Jan 15;87(2):423–438. [PubMed] [Google Scholar]
- Uziel T., Savitsky K., Platzer M., Ziv Y., Helbitz T., Nehls M., Boehm T., Rosenthal A., Shiloh Y., Rotman G. Genomic Organization of the ATM gene. Genomics. 1996 Apr 15;33(2):317–320. doi: 10.1006/geno.1996.0201. [DOI] [PubMed] [Google Scholar]