Abstract
The 18q- syndrome is one of several terminal deletion disorders that occur in humans. Previous G-banding studies suggest that the loss of a critical band, 18q21.3, results in mental retardation, craniofacial anomalies, and metabolic defects. However, it is difficult to reconcile the consistent loss of a single region with the large variability in clinical phenotype. The purpose of this study was to reassess the extent of chromosomal loss in a cohort of 17 18q- syndrome patients by using fluorescent-activated chromosome sorting, PCR, and FISH. Bivariate flow karyotypes revealed heterogeneity among the deletions; they ranged in size from 9 to 26 Mb. To confirm this heterogeneity at a molecular level, deleted and normal chromosomes 18 of six patients were collected by flow sorting, preamplified by random priming, and assayed for marker content by the PCR. This analysis defined five unique breakpoints among the six patients. We conclude that the terminal deletions in the 18q- syndrome occur over a broad region spanning the interval from 18q21.2 to 18q22.2. Our results suggest that the variability in clinical phenotype may be more representative of a contiguous-gene syndrome with a baseline deficit of 18q22.2-qter than of the loss of a single critical region within 18q21.3.
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- Barbarese E., Nielson M. L., Carson J. H. The effect of the shiverer mutation on myelin basic protein expression in homozygous and heterozygous mouse brain. J Neurochem. 1983 Jun;40(6):1680–1686. doi: 10.1111/j.1471-4159.1983.tb08142.x. [DOI] [PubMed] [Google Scholar]
- Brack-Werner R., Barton D. E., Werner T., Foellmer B. E., Leib-Mösch C., Francke U., Erfle V., Hehlmann R. Human SSAV-related endogenous retroviral element: LTR-like sequence and chromosomal localization to 18q21. Genomics. 1989 Jan;4(1):68–75. doi: 10.1016/0888-7543(89)90316-9. [DOI] [PubMed] [Google Scholar]
- Brenner D. A., Didier J. M., Frasier F., Christensen S. R., Evans G. A., Dailey H. A. A molecular defect in human protoporphyria. Am J Hum Genet. 1992 Jun;50(6):1203–1210. [PMC free article] [PubMed] [Google Scholar]
- Cammer W., Kahn S., Zimmerman T. Biochemical abnormalities in spinal cord myelin and CNS homogenates in heterozygotes affected by the shiverer mutation. J Neurochem. 1984 May;42(5):1372–1378. doi: 10.1111/j.1471-4159.1984.tb02797.x. [DOI] [PubMed] [Google Scholar]
- Chasalow F. I., Blethen S. L., Knight S. M., Taysi K. 18q deletion syndrome in a child with steroid-17,20-lyase deficiency. Steroids. 1986 Jun;47(6):421–429. doi: 10.1016/0039-128x(86)90057-7. [DOI] [PubMed] [Google Scholar]
- DE GROUCHY J., ROYER P., SALMON C., LAMY M. D'EL'ETION PARTIELLE DES BRAS LONGS DU CHROMOSOME 18. Pathol Biol. 1964 May;12:579–582. [PubMed] [Google Scholar]
- Emanuel B. S. Molecular cytogenetics: toward dissection of the contiguous gene syndromes. Am J Hum Genet. 1988 Nov;43(5):575–578. [PMC free article] [PubMed] [Google Scholar]
- Fearon E. R., Cho K. R., Nigro J. M., Kern S. E., Simons J. W., Ruppert J. M., Hamilton S. R., Preisinger A. C., Thomas G., Kinzler K. W. Identification of a chromosome 18q gene that is altered in colorectal cancers. Science. 1990 Jan 5;247(4938):49–56. doi: 10.1126/science.2294591. [DOI] [PubMed] [Google Scholar]
- Felding I., Kristoffersson U., Sjöström H., Norén O. Contribution to the 18q- syndrome. A patient with del(18) (q22.3qter). Clin Genet. 1987 Apr;31(4):206–210. doi: 10.1111/j.1399-0004.1987.tb02797.x. [DOI] [PubMed] [Google Scholar]
- Finley S. C., Cooper M. D., Finley W. H., Uchida I. A., Noto T. A., Roddam R. F. Immunological profile in a chromosome 18 deletion syndrome with IgA deficiency. J Med Genet. 1969 Dec;6(4):388–393. doi: 10.1136/jmg.6.4.388. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Francke U. Digitized and differentially shaded human chromosome ideograms for genomic applications. Cytogenet Cell Genet. 1994;65(3):206–218. doi: 10.1159/000133633. [DOI] [PubMed] [Google Scholar]
- Gyapay G., Morissette J., Vignal A., Dib C., Fizames C., Millasseau P., Marc S., Bernardi G., Lathrop M., Weissenbach J. The 1993-94 Généthon human genetic linkage map. Nat Genet. 1994 Jun;7(2 Spec No):246–339. doi: 10.1038/ng0694supp-246. [DOI] [PubMed] [Google Scholar]
- Henrot B., Ninane J., Mercenier C., Vermylen C., Verellen C., Cornu G., Malvaux P. Délétion du bras long du chromosome 18, hypothyroïdie primaire, anémie de Biermer et hypogammaglobulinémie de type IgM. Arch Fr Pediatr. 1989 Dec;46(10):729–732. [PubMed] [Google Scholar]
- Hindi A., Beneck D., Greco M. A., Wolman S. R. 18q+, the progeny of a balanced translocation t(1;18)mat: case report with necropsy findings. J Med Genet. 1986 Jun;23(3):263–266. doi: 10.1136/jmg.23.3.263. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kline A. D., White M. E., Wapner R., Rojas K., Biesecker L. G., Kamholz J., Zackai E. H., Muenke M., Scott C. I., Jr, Overhauser J. Molecular analysis of the 18q- syndrome--and correlation with phenotype. Am J Hum Genet. 1993 May;52(5):895–906. [PMC free article] [PubMed] [Google Scholar]
- Kristjansson K., Chong S. S., Van den Veyver I. B., Subramanian S., Snabes M. C., Hughes M. R. Preimplantation single cell analyses of dystrophin gene deletions using whole genome amplification. Nat Genet. 1994 Jan;6(1):19–23. doi: 10.1038/ng0194-19. [DOI] [PubMed] [Google Scholar]
- Kroisel P. M., Ioannou P. A., de Jong P. J. PCR probes for chromosome in situ hybridization of large-insert bacterial recombinants. Cytogenet Cell Genet. 1994;65(1-2):97–100. doi: 10.1159/000133609. [DOI] [PubMed] [Google Scholar]
- Le Beau M. M., Overhauser J., Straub R. E., Silverman G., Gilliam T. C., Ott J., O'Connell P., Francke U., Geurts van Kessel A. Report of the first international workshop on human chromosome 18 mapping. Cytogenet Cell Genet. 1993;63(2):78–96. [PubMed] [Google Scholar]
- Lejeune J., Berger R., Lafourcade J., Réthoré M. O. La délétion partielle du bras long du chromosome 18. Individualisation d'un nouvel état morbide. Ann Genet. 1966;9(1):32–38. [PubMed] [Google Scholar]
- Lurie I. W., Lazjuk G. I. Partial monosomies 18. Review of cytogenetical and phenotypical variants. Humangenetik. 1972;15(3):203–222. doi: 10.1007/BF00702354. [DOI] [PubMed] [Google Scholar]
- Magness S. T., Tugores A., Christensen S. R., Wagner-Mcpherson C., Evans G. A., Naylor E. W., Brenner D. A. Deletion of the ferrochelatase gene in a patient with protoporphyria. Hum Mol Genet. 1994 Sep;3(9):1695–1697. doi: 10.1093/hmg/3.9.1695. [DOI] [PubMed] [Google Scholar]
- Miller G., Mowrey P. N., Hopper K. D., Frankel C. A., Ladda R. L. Neurologic manifestations in 18q- syndrome. Am J Med Genet. 1990 Sep;37(1):128–132. doi: 10.1002/ajmg.1320370130. [DOI] [PubMed] [Google Scholar]
- Naylor E. W., Murphey W. H., Domoszlai E. I., Guthrie R. Erythropoietic protoporphyria, heterozygous cystinuria, and reduced peptidase A activity in a patient with 46,XX/46,XX,18q--mosaicism. J Med Genet. 1978 Apr;15(2):157–160. doi: 10.1136/jmg.15.2.157. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Roa B. B., Garcia C. A., Pentao L., Killian J. M., Trask B. J., Suter U., Snipes G. J., Ortiz-Lopez R., Shooter E. M., Patel P. I. Evidence for a recessive PMP22 point mutation in Charcot-Marie-Tooth disease type 1A. Nat Genet. 1993 Oct;5(2):189–194. doi: 10.1038/ng1093-189. [DOI] [PubMed] [Google Scholar]
- Roach A., Takahashi N., Pravtcheva D., Ruddle F., Hood L. Chromosomal mapping of mouse myelin basic protein gene and structure and transcription of the partially deleted gene in shiverer mutant mice. Cell. 1985 Aug;42(1):149–155. doi: 10.1016/s0092-8674(85)80110-0. [DOI] [PubMed] [Google Scholar]
- Schinzel A., Hayashi K., Schmid W. Structural aberrations of chromosome 18. II. The 18q- syndrome. Report of three cases. Humangenetik. 1975;26(2):123–132. [PubMed] [Google Scholar]
- Schmickel R. D. Contiguous gene syndromes: a component of recognizable syndromes. J Pediatr. 1986 Aug;109(2):231–241. doi: 10.1016/s0022-3476(86)80377-8. [DOI] [PubMed] [Google Scholar]
- Silverman G. A., Jockel J. I., Domer P. H., Mohr R. M., Taillon-Miller P., Korsmeyer S. J. Yeast artificial chromosome cloning of a two-megabase-size contig within chromosomal band 18q21 establishes physical linkage between BCL2 and plasminogen activator inhibitor type-2. Genomics. 1991 Feb;9(2):219–228. doi: 10.1016/0888-7543(91)90245-a. [DOI] [PubMed] [Google Scholar]
- Silverman G. A., Kuo W. L., Taillon-Miller P., Gray J. W. Chromosomal reassignment: YACs containing both YES1 and thymidylate synthase map to the short arm of chromosome 18. Genomics. 1993 Feb;15(2):442–445. doi: 10.1006/geno.1993.1086. [DOI] [PubMed] [Google Scholar]
- Silverman G. A., Yang E., Proffitt J. H., Zutter M., Korsmeyer S. J. Genetic transfer and expression of reconstructed yeast artificial chromosomes containing normal and translocated BCL2 proto-oncogenes. Mol Cell Biol. 1993 Sep;13(9):5469–5478. doi: 10.1128/mcb.13.9.5469. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Strathdee G., Harrison W., Riethman H. C., Goodart S. A., Overhauser J. Interstitial deletions are not the main mechanism leading to 18q deletions. Am J Hum Genet. 1994 Jun;54(6):1085–1091. [PMC free article] [PubMed] [Google Scholar]
- Stricker R. B., Linker C. A. Pernicious anemia, 18q deletion syndrome, and IgA deficiency. JAMA. 1982 Sep 17;248(11):1359–1360. [PubMed] [Google Scholar]
- Sugden B., Mark W. Clonal transformation of adult human leukocytes by Epstein-Barr virus. J Virol. 1977 Sep;23(3):503–508. doi: 10.1128/jvi.23.3.503-508.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Telenius H., Carter N. P., Bebb C. E., Nordenskjöld M., Ponder B. A., Tunnacliffe A. Degenerate oligonucleotide-primed PCR: general amplification of target DNA by a single degenerate primer. Genomics. 1992 Jul;13(3):718–725. doi: 10.1016/0888-7543(92)90147-k. [DOI] [PubMed] [Google Scholar]
- Telenius H., Pelmear A. H., Tunnacliffe A., Carter N. P., Behmel A., Ferguson-Smith M. A., Nordenskjöld M., Pfragner R., Ponder B. A. Cytogenetic analysis by chromosome painting using DOP-PCR amplified flow-sorted chromosomes. Genes Chromosomes Cancer. 1992 Apr;4(3):257–263. doi: 10.1002/gcc.2870040311. [DOI] [PubMed] [Google Scholar]
- Trask B., van den Engh G., Mayall B., Gray J. W. Chromosome heteromorphism quantified by high-resolution bivariate flow karyotyping. Am J Hum Genet. 1989 Nov;45(5):739–752. [PMC free article] [PubMed] [Google Scholar]
- Trask B., van den Engh G., Nussbaum R., Schwartz C., Gray J. Quantification of the DNA content of structurally abnormal X chromosomes and X chromosome aneuploidy using high resolution bivariate flow karyotyping. Cytometry. 1990;11(1):184–195. doi: 10.1002/cyto.990110121. [DOI] [PubMed] [Google Scholar]
- VanDevanter D. R., Choongkittaworn N. M., Dyer K. A., Aten J., Otto P., Behler C., Bryant E. M., Rabinovitch P. S. Pure chromosome-specific PCR libraries from single sorted chromosomes. Proc Natl Acad Sci U S A. 1994 Jun 21;91(13):5858–5862. doi: 10.1073/pnas.91.13.5858. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vogel H., Urich H., Horoupian D. S., Wertelecki W. The brain in the 18q-syndrome. Dev Med Child Neurol. 1990 Aug;32(8):732–737. doi: 10.1111/j.1469-8749.1990.tb08435.x. [DOI] [PubMed] [Google Scholar]
- Wertelecki W., Gerald P. S. Clinical and chromosomal studies of the 18q- syndrome. J Pediatr. 1971 Jan;78(1):44–52. doi: 10.1016/s0022-3476(71)80262-7. [DOI] [PubMed] [Google Scholar]
- Wilson M. G., Towner J. W., Forsman I., Siris E. Syndromes associated with deletion of the long arm of chromosome 18[del(18q)]. Am J Med Genet. 1979;3(2):155–174. doi: 10.1002/ajmg.1320030207. [DOI] [PubMed] [Google Scholar]
- Zhang L., Cui X., Schmitt K., Hubert R., Navidi W., Arnheim N. Whole genome amplification from a single cell: implications for genetic analysis. Proc Natl Acad Sci U S A. 1992 Jul 1;89(13):5847–5851. doi: 10.1073/pnas.89.13.5847. [DOI] [PMC free article] [PubMed] [Google Scholar]
- van Kessel A. G., Straub R. E., Silverman G. A., Gerken S., Overhauser J. Report and abstracts of the second international workshop on human chromosome 18 mapping. Doorwerth, the Netherlands, July 19-20, 1993. Cytogenet Cell Genet. 1994;65(3):142–165. [PubMed] [Google Scholar]


