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American Journal of Human Genetics logoLink to American Journal of Human Genetics
. 1995 Jan;56(1):106–113.

Quantitative comparison of FMR1 gene expression in normal and premutation alleles.

Y Feng 1, L Lakkis 1, D Devys 1, S T Warren 1
PMCID: PMC1801331  PMID: 7825564

Abstract

We report studies on FMR1 gene expression in cells derived from male premutation carriers. Transcription of FMR1 genes with CGG-repeat lengths within the premutation range was demonstrated to be normal. Repeat lengths are faithfully transcribed into FMR1 mRNAs, which have steady-state levels, as measured by RNase protection, similar to those of normal cells. Premutation transcripts also are shown to have normal turnover, with the FMR1 mRNA half-life estimated to be 12 h. Measurement of FMR1 protein was also found to be in similar abundance in normal and premutation cell lines. These data support the nonpenetrant status of premutation carriers of fragile X syndrome and suggest that the occasional case reports to the contrary may reflect either other causes, including low-level mosaicism for larger, methylated FMR1 alleles, or simply coincidence.

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Selected References

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  1. Ashley C. T., Sutcliffe J. S., Kunst C. B., Leiner H. A., Eichler E. E., Nelson D. L., Warren S. T. Human and murine FMR-1: alternative splicing and translational initiation downstream of the CGG-repeat. Nat Genet. 1993 Jul;4(3):244–251. doi: 10.1038/ng0793-244. [DOI] [PubMed] [Google Scholar]
  2. Brown W. T., Houck G. E., Jr, Jeziorowska A., Levinson F. N., Ding X., Dobkin C., Zhong N., Henderson J., Brooks S. S., Jenkins E. C. Rapid fragile X carrier screening and prenatal diagnosis using a nonradioactive PCR test. JAMA. 1993 Oct 6;270(13):1569–1575. [PubMed] [Google Scholar]
  3. Chomczynski P., Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal Biochem. 1987 Apr;162(1):156–159. doi: 10.1006/abio.1987.9999. [DOI] [PubMed] [Google Scholar]
  4. Cronister A., Schreiner R., Wittenberger M., Amiri K., Harris K., Hagerman R. J. Heterozygous fragile X female: historical, physical, cognitive, and cytogenetic features. Am J Med Genet. 1991 Feb-Mar;38(2-3):269–274. doi: 10.1002/ajmg.1320380221. [DOI] [PubMed] [Google Scholar]
  5. Devys D., Lutz Y., Rouyer N., Bellocq J. P., Mandel J. L. The FMR-1 protein is cytoplasmic, most abundant in neurons and appears normal in carriers of a fragile X premutation. Nat Genet. 1993 Aug;4(4):335–340. doi: 10.1038/ng0893-335. [DOI] [PubMed] [Google Scholar]
  6. Dorn M. B., Mazzocco M. M., Hagerman R. J. Behavioral and psychiatric disorders in adult male carriers of fragile X. J Am Acad Child Adolesc Psychiatry. 1994 Feb;33(2):256–264. doi: 10.1097/00004583-199402000-00015. [DOI] [PubMed] [Google Scholar]
  7. Eichler E. E., Richards S., Gibbs R. A., Nelson D. L. Fine structure of the human FMR1 gene. Hum Mol Genet. 1993 Aug;2(8):1147–1153. doi: 10.1093/hmg/2.8.1147. [DOI] [PubMed] [Google Scholar]
  8. Feng Y., Gunter L. E., Organ E. L., Cavener D. R. Translation initiation in Drosophila melanogaster is reduced by mutations upstream of the AUG initiator codon. Mol Cell Biol. 1991 Apr;11(4):2149–2153. doi: 10.1128/mcb.11.4.2149. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Feng Y., Schiff N. M., Cavener D. R. Organ-specific patterns of gene expression in the reproductive tract of Drosophila are regulated by the sex-determination genes. Dev Biol. 1991 Aug;146(2):451–460. doi: 10.1016/0012-1606(91)90246-y. [DOI] [PubMed] [Google Scholar]
  10. Fort P., Marty L., Piechaczyk M., el Sabrouty S., Dani C., Jeanteur P., Blanchard J. M. Various rat adult tissues express only one major mRNA species from the glyceraldehyde-3-phosphate-dehydrogenase multigenic family. Nucleic Acids Res. 1985 Mar 11;13(5):1431–1442. doi: 10.1093/nar/13.5.1431. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Fu Y. H., Kuhl D. P., Pizzuti A., Pieretti M., Sutcliffe J. S., Richards S., Verkerk A. J., Holden J. J., Fenwick R. G., Jr, Warren S. T. Variation of the CGG repeat at the fragile X site results in genetic instability: resolution of the Sherman paradox. Cell. 1991 Dec 20;67(6):1047–1058. doi: 10.1016/0092-8674(91)90283-5. [DOI] [PubMed] [Google Scholar]
  12. García Conejero O., Gené Badia J., Parellada Esquius N. Ley del "cuidado inverso" en la detección de la hipertensión arterial y el tabaquismo. Aten Primaria. 1992 Jun 1;9(9):496–498. [PubMed] [Google Scholar]
  13. Gedeon A. K., Baker E., Robinson H., Partington M. W., Gross B., Manca A., Korn B., Poustka A., Yu S., Sutherland G. R. Fragile X syndrome without CCG amplification has an FMR1 deletion. Nat Genet. 1992 Aug;1(5):341–344. doi: 10.1038/ng0892-341. [DOI] [PubMed] [Google Scholar]
  14. Gunning P., Ponte P., Okayama H., Engel J., Blau H., Kedes L. Isolation and characterization of full-length cDNA clones for human alpha-, beta-, and gamma-actin mRNAs: skeletal but not cytoplasmic actins have an amino-terminal cysteine that is subsequently removed. Mol Cell Biol. 1983 May;3(5):787–795. doi: 10.1128/mcb.3.5.787. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Hansen R. S., Gartler S. M., Scott C. R., Chen S. H., Laird C. D. Methylation analysis of CGG sites in the CpG island of the human FMR1 gene. Hum Mol Genet. 1992 Nov;1(8):571–578. doi: 10.1093/hmg/1.8.571. [DOI] [PubMed] [Google Scholar]
  16. Heitz D., Devys D., Imbert G., Kretz C., Mandel J. L. Inheritance of the fragile X syndrome: size of the fragile X premutation is a major determinant of the transition to full mutation. J Med Genet. 1992 Nov;29(11):794–801. doi: 10.1136/jmg.29.11.794. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Heitz D., Rousseau F., Devys D., Saccone S., Abderrahim H., Le Paslier D., Cohen D., Vincent A., Toniolo D., Della Valle G. Isolation of sequences that span the fragile X and identification of a fragile X-related CpG island. Science. 1991 Mar 8;251(4998):1236–1239. doi: 10.1126/science.2006411. [DOI] [PubMed] [Google Scholar]
  18. Hinds H. L., Ashley C. T., Sutcliffe J. S., Nelson D. L., Warren S. T., Housman D. E., Schalling M. Tissue specific expression of FMR-1 provides evidence for a functional role in fragile X syndrome. Nat Genet. 1993 Jan;3(1):36–43. doi: 10.1038/ng0193-36. [DOI] [PubMed] [Google Scholar]
  19. Hornstra I. K., Nelson D. L., Warren S. T., Yang T. P. High resolution methylation analysis of the FMR1 gene trinucleotide repeat region in fragile X syndrome. Hum Mol Genet. 1993 Oct;2(10):1659–1665. doi: 10.1093/hmg/2.10.1659. [DOI] [PubMed] [Google Scholar]
  20. Hull C., Hagerman R. J. A study of the physical, behavioral, and medical phenotype, including anthropometric measures, of females with fragile X syndrome. Am J Dis Child. 1993 Nov;147(11):1236–1241. doi: 10.1001/archpedi.1993.02160350110017. [DOI] [PubMed] [Google Scholar]
  21. Joshi H. C., Cleveland D. W. Differential utilization of beta-tubulin isotypes in differentiating neurites. J Cell Biol. 1989 Aug;109(2):663–673. doi: 10.1083/jcb.109.2.663. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Krasney P. A., Carr C., Cavener D. R. Evolution of the glucose dehydrogenase gene in Drosophila. Mol Biol Evol. 1990 Mar;7(2):155–177. doi: 10.1093/oxfordjournals.molbev.a040592. [DOI] [PubMed] [Google Scholar]
  23. Kremer E. J., Pritchard M., Lynch M., Yu S., Holman K., Baker E., Warren S. T., Schlessinger D., Sutherland G. R., Richards R. I. Mapping of DNA instability at the fragile X to a trinucleotide repeat sequence p(CCG)n. Science. 1991 Jun 21;252(5013):1711–1714. doi: 10.1126/science.1675488. [DOI] [PubMed] [Google Scholar]
  24. Krowczynska A., Yenofsky R., Brawerman G. Regulation of messenger RNA stability in mouse erythroleukemia cells. J Mol Biol. 1985 Jan 20;181(2):231–239. doi: 10.1016/0022-2836(85)90087-7. [DOI] [PubMed] [Google Scholar]
  25. Kunst C. B., Warren S. T. Cryptic and polar variation of the fragile X repeat could result in predisposing normal alleles. Cell. 1994 Jun 17;77(6):853–861. doi: 10.1016/0092-8674(94)90134-1. [DOI] [PubMed] [Google Scholar]
  26. Litt M., Hauge X., Sharma V. Shadow bands seen when typing polymorphic dinucleotide repeats: some causes and cures. Biotechniques. 1993 Aug;15(2):280–284. [PubMed] [Google Scholar]
  27. Loesch D. Z., Huggins R., Hay D. A., Gedeon A. K., Mulley J. C., Sutherland G. R. Genotype-phenotype relationships in fragile X syndrome: a family study. Am J Hum Genet. 1993 Nov;53(5):1064–1073. [PMC free article] [PubMed] [Google Scholar]
  28. Mazzocco M. M., Pennington B. F., Hagerman R. J. The neurocognitive phenotype of female carriers of fragile X: additional evidence for specificity. J Dev Behav Pediatr. 1993 Oct;14(5):328–335. [PubMed] [Google Scholar]
  29. McConkie-Rosell A., Lachiewicz A. M., Spiridigliozzi G. A., Tarleton J., Schoenwald S., Phelan M. C., Goonewardena P., Ding X., Brown W. T. Evidence that methylation of the FMR-I locus is responsible for variable phenotypic expression of the fragile X syndrome. Am J Hum Genet. 1993 Oct;53(4):800–809. [PMC free article] [PubMed] [Google Scholar]
  30. Meijer H., de Graaff E., Merckx D. M., Jongbloed R. J., de Die-Smulders C. E., Engelen J. J., Fryns J. P., Curfs P. M., Oostra B. A. A deletion of 1.6 kb proximal to the CGG repeat of the FMR1 gene causes the clinical phenotype of the fragile X syndrome. Hum Mol Genet. 1994 Apr;3(4):615–620. doi: 10.1093/hmg/3.4.615. [DOI] [PubMed] [Google Scholar]
  31. Oberlé I., Rousseau F., Heitz D., Kretz C., Devys D., Hanauer A., Boué J., Bertheas M. F., Mandel J. L. Instability of a 550-base pair DNA segment and abnormal methylation in fragile X syndrome. Science. 1991 May 24;252(5009):1097–1102. doi: 10.1126/science.252.5009.1097. [DOI] [PubMed] [Google Scholar]
  32. Pieretti M., Zhang F. P., Fu Y. H., Warren S. T., Oostra B. A., Caskey C. T., Nelson D. L. Absence of expression of the FMR-1 gene in fragile X syndrome. Cell. 1991 Aug 23;66(4):817–822. doi: 10.1016/0092-8674(91)90125-i. [DOI] [PubMed] [Google Scholar]
  33. Reiss A. L., Freund L., Abrams M. T., Boehm C., Kazazian H. Neurobehavioral effects of the fragile X premutation in adult women: a controlled study. Am J Hum Genet. 1993 May;52(5):884–894. [PMC free article] [PubMed] [Google Scholar]
  34. Riggins G. J., Lokey L. K., Chastain J. L., Leiner H. A., Sherman S. L., Wilkinson K. D., Warren S. T. Human genes containing polymorphic trinucleotide repeats. Nat Genet. 1992 Nov;2(3):186–191. doi: 10.1038/ng1192-186. [DOI] [PubMed] [Google Scholar]
  35. Rousseau F., Heitz D., Tarleton J., MacPherson J., Malmgren H., Dahl N., Barnicoat A., Mathew C., Mornet E., Tejada I. A multicenter study on genotype-phenotype correlations in the fragile X syndrome, using direct diagnosis with probe StB12.3: the first 2,253 cases. Am J Hum Genet. 1994 Aug;55(2):225–237. [PMC free article] [PubMed] [Google Scholar]
  36. Siomi H., Siomi M. C., Nussbaum R. L., Dreyfuss G. The protein product of the fragile X gene, FMR1, has characteristics of an RNA-binding protein. Cell. 1993 Jul 30;74(2):291–298. doi: 10.1016/0092-8674(93)90420-u. [DOI] [PubMed] [Google Scholar]
  37. Smits A. P., Dreesen J. C., Post J. G., Smeets D. F., de Die-Smulders C., Spaans-van der Bijl T., Govaerts L. C., Warren S. T., Oostra B. A., van Oost B. A. The fragile X syndrome: no evidence for any recent mutations. J Med Genet. 1993 Feb;30(2):94–96. doi: 10.1136/jmg.30.2.94. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Snow K., Doud L. K., Hagerman R., Pergolizzi R. G., Erster S. H., Thibodeau S. N. Analysis of a CGG sequence at the FMR-1 locus in fragile X families and in the general population. Am J Hum Genet. 1993 Dec;53(6):1217–1228. [PMC free article] [PubMed] [Google Scholar]
  39. Sobesky W. E., Hull C. E., Hagerman R. J. Symptoms of schizotypal personality disorder in fragile X women. J Am Acad Child Adolesc Psychiatry. 1994 Feb;33(2):247–255. doi: 10.1097/00004583-199402000-00014. [DOI] [PubMed] [Google Scholar]
  40. Steinbach P., Wöhrle D., Tariverdian G., Kennerknecht I., Barbi G., Edlinger H., Enders H., Götz-Sothmann M., Heilbronner H., Hosenfeld D. Molecular analysis of mutations in the gene FMR-1 segregating in fragile X families. Hum Genet. 1993 Nov;92(5):491–498. doi: 10.1007/BF00216457. [DOI] [PubMed] [Google Scholar]
  41. Steyaert J., Borghgraef M., Gaulthier C., Fryns J. P., Van den Berghe H. Cognitive profile in adult, normal intelligent female fragile X carriers. 1992 Apr 15-May 1Am J Med Genet. 43(1-2):116–119. doi: 10.1002/ajmg.1320430117. [DOI] [PubMed] [Google Scholar]
  42. Sutcliffe J. S., Nelson D. L., Zhang F., Pieretti M., Caskey C. T., Saxe D., Warren S. T. DNA methylation represses FMR-1 transcription in fragile X syndrome. Hum Mol Genet. 1992 Sep;1(6):397–400. doi: 10.1093/hmg/1.6.397. [DOI] [PubMed] [Google Scholar]
  43. Taylor A. K., Safanda J. F., Fall M. Z., Quince C., Lang K. A., Hull C. E., Carpenter I., Staley L. W., Hagerman R. J. Molecular predictors of cognitive involvement in female carriers of fragile X syndrome. JAMA. 1994 Feb 16;271(7):507–514. [PubMed] [Google Scholar]
  44. Verheij C., Bakker C. E., de Graaff E., Keulemans J., Willemsen R., Verkerk A. J., Galjaard H., Reuser A. J., Hoogeveen A. T., Oostra B. A. Characterization and localization of the FMR-1 gene product associated with fragile X syndrome. Nature. 1993 Jun 24;363(6431):722–724. doi: 10.1038/363722a0. [DOI] [PubMed] [Google Scholar]
  45. Verkerk A. J., Pieretti M., Sutcliffe J. S., Fu Y. H., Kuhl D. P., Pizzuti A., Reiner O., Richards S., Victoria M. F., Zhang F. P. Identification of a gene (FMR-1) containing a CGG repeat coincident with a breakpoint cluster region exhibiting length variation in fragile X syndrome. Cell. 1991 May 31;65(5):905–914. doi: 10.1016/0092-8674(91)90397-h. [DOI] [PubMed] [Google Scholar]
  46. Warren S. T., Ashley C. T., Jr Triplet repeat expansion mutations: the example of fragile X syndrome. Annu Rev Neurosci. 1995;18:77–99. doi: 10.1146/annurev.ne.18.030195.000453. [DOI] [PubMed] [Google Scholar]
  47. Warren S. T., Nelson D. L. Advances in molecular analysis of fragile X syndrome. JAMA. 1994 Feb 16;271(7):536–542. [PubMed] [Google Scholar]
  48. Wöhrle D., Kotzot D., Hirst M. C., Manca A., Korn B., Schmidt A., Barbi G., Rott H. D., Poustka A., Davies K. E. A microdeletion of less than 250 kb, including the proximal part of the FMR-I gene and the fragile-X site, in a male with the clinical phenotype of fragile-X syndrome. Am J Hum Genet. 1992 Aug;51(2):299–306. [PMC free article] [PubMed] [Google Scholar]
  49. Yu S., Mulley J., Loesch D., Turner G., Donnelly A., Gedeon A., Hillen D., Kremer E., Lynch M., Pritchard M. Fragile-X syndrome: unique genetics of the heritable unstable element. Am J Hum Genet. 1992 May;50(5):968–980. [PMC free article] [PubMed] [Google Scholar]
  50. Yu S., Pritchard M., Kremer E., Lynch M., Nancarrow J., Baker E., Holman K., Mulley J. C., Warren S. T., Schlessinger D. Fragile X genotype characterized by an unstable region of DNA. Science. 1991 May 24;252(5009):1179–1181. doi: 10.1126/science.252.5009.1179. [DOI] [PubMed] [Google Scholar]

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