Abstract
The fragile X syndrome (FXS) is caused by silencing of the fragile X mental retardation gene (FMR1) and the absence of its product, fragile X mental retardation protein (FMRP), resulting from CpG island methylation associated with large CGG repeat expansions (more than 200) termed full mutation (FM). We have identified a number of novel epigenetic markers for FXS using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), naming the most informative fragile X-related epigenetic element 1 (FREE1) and 2 (FREE2). Methylation of both regions was correlated with that of the FMR1 CpG island detected using Southern blot (FREE1 R = 0.97; P < 0.00001, n = 23 and FREE2 R = 0.93; P < 0.00001, n = 23) and nega- tively correlated with lymphocyte expression of FMRP (FREE1 R 520.62; P = 0.01, n = 15 and FREE2 R 520.55; P = 0.03, n = 15) in blood of partially methylated 'high functioning' FM males. In blood of FM carrier females, methylation of both markers was inversely correlated with the FMR1 activation ratio (FREE1 R 520.93; P < 0.0001, n = 12 and FREE2 R 520.95; P < 0.0001, n = 9). In a sample set of 49 controls, 18 grey zone (GZ 40-54 repeats), 22 premutation (PM 55-170 repeats) and 22 (affected) FXS subjects, the FREE1 methylation pattern was consistent between blood and chorionic villi as a marker of methylated FM alleles and could be used to differentiate FXS males and females from controls, as well as from carriers of GZ/PM alleles, but not between GZ and PM alleles and controls. Considering its high-throughput and speci- ficity for pathogenic FM alleles, low cost and minimal DNA requirements, FREE MALDI-TOF MS offers a unique tool in FXS diagnostics and newborn population screening.
| Original language | English (US) |
|---|---|
| Article number | ddq037 |
| Pages (from-to) | 1618-1632 |
| Number of pages | 15 |
| Journal | Human Molecular Genetics |
| Volume | 19 |
| Issue number | 8 |
| DOIs | |
| State | Published - Jan 29 2010 |
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ASJC Scopus subject areas
- Genetics
- Genetics(clinical)
- Molecular Biology
Cite this
Methylation of novel markers of fragile X alleles is inversely correlated with FMRP expression and FMR1 activation ratio. / Godler, David Eugeny; Tassone, Flora; Loesch, Danuta Zuzanna; Taylor, Annette Kimball; Gehling, Freya; Hagerman, Randi J; Burgess, Trent; Ganesamoorthy, Devika; Hennerich, Debbie; Gordon, Lavinia; Evans, Andrew; Choo, K. H.; Slater, Howard Robert.
In: Human Molecular Genetics, Vol. 19, No. 8, ddq037, 29.01.2010, p. 1618-1632.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Methylation of novel markers of fragile X alleles is inversely correlated with FMRP expression and FMR1 activation ratio
AU - Godler, David Eugeny
AU - Tassone, Flora
AU - Loesch, Danuta Zuzanna
AU - Taylor, Annette Kimball
AU - Gehling, Freya
AU - Hagerman, Randi J
AU - Burgess, Trent
AU - Ganesamoorthy, Devika
AU - Hennerich, Debbie
AU - Gordon, Lavinia
AU - Evans, Andrew
AU - Choo, K. H.
AU - Slater, Howard Robert
PY - 2010/1/29
Y1 - 2010/1/29
N2 - The fragile X syndrome (FXS) is caused by silencing of the fragile X mental retardation gene (FMR1) and the absence of its product, fragile X mental retardation protein (FMRP), resulting from CpG island methylation associated with large CGG repeat expansions (more than 200) termed full mutation (FM). We have identified a number of novel epigenetic markers for FXS using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), naming the most informative fragile X-related epigenetic element 1 (FREE1) and 2 (FREE2). Methylation of both regions was correlated with that of the FMR1 CpG island detected using Southern blot (FREE1 R = 0.97; P < 0.00001, n = 23 and FREE2 R = 0.93; P < 0.00001, n = 23) and nega- tively correlated with lymphocyte expression of FMRP (FREE1 R 520.62; P = 0.01, n = 15 and FREE2 R 520.55; P = 0.03, n = 15) in blood of partially methylated 'high functioning' FM males. In blood of FM carrier females, methylation of both markers was inversely correlated with the FMR1 activation ratio (FREE1 R 520.93; P < 0.0001, n = 12 and FREE2 R 520.95; P < 0.0001, n = 9). In a sample set of 49 controls, 18 grey zone (GZ 40-54 repeats), 22 premutation (PM 55-170 repeats) and 22 (affected) FXS subjects, the FREE1 methylation pattern was consistent between blood and chorionic villi as a marker of methylated FM alleles and could be used to differentiate FXS males and females from controls, as well as from carriers of GZ/PM alleles, but not between GZ and PM alleles and controls. Considering its high-throughput and speci- ficity for pathogenic FM alleles, low cost and minimal DNA requirements, FREE MALDI-TOF MS offers a unique tool in FXS diagnostics and newborn population screening.
AB - The fragile X syndrome (FXS) is caused by silencing of the fragile X mental retardation gene (FMR1) and the absence of its product, fragile X mental retardation protein (FMRP), resulting from CpG island methylation associated with large CGG repeat expansions (more than 200) termed full mutation (FM). We have identified a number of novel epigenetic markers for FXS using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), naming the most informative fragile X-related epigenetic element 1 (FREE1) and 2 (FREE2). Methylation of both regions was correlated with that of the FMR1 CpG island detected using Southern blot (FREE1 R = 0.97; P < 0.00001, n = 23 and FREE2 R = 0.93; P < 0.00001, n = 23) and nega- tively correlated with lymphocyte expression of FMRP (FREE1 R 520.62; P = 0.01, n = 15 and FREE2 R 520.55; P = 0.03, n = 15) in blood of partially methylated 'high functioning' FM males. In blood of FM carrier females, methylation of both markers was inversely correlated with the FMR1 activation ratio (FREE1 R 520.93; P < 0.0001, n = 12 and FREE2 R 520.95; P < 0.0001, n = 9). In a sample set of 49 controls, 18 grey zone (GZ 40-54 repeats), 22 premutation (PM 55-170 repeats) and 22 (affected) FXS subjects, the FREE1 methylation pattern was consistent between blood and chorionic villi as a marker of methylated FM alleles and could be used to differentiate FXS males and females from controls, as well as from carriers of GZ/PM alleles, but not between GZ and PM alleles and controls. Considering its high-throughput and speci- ficity for pathogenic FM alleles, low cost and minimal DNA requirements, FREE MALDI-TOF MS offers a unique tool in FXS diagnostics and newborn population screening.
UR - http://www.scopus.com/inward/record.url?scp=77952304162&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77952304162&partnerID=8YFLogxK
U2 - 10.1093/hmg/ddq037
DO - 10.1093/hmg/ddq037
M3 - Article
C2 - 20118148
AN - SCOPUS:77952304162
VL - 19
SP - 1618
EP - 1632
JO - Human Molecular Genetics
JF - Human Molecular Genetics
SN - 0964-6906
IS - 8
M1 - ddq037
ER -