TY - JOUR
T1 - The 5-methylcytosine content of highly repeated sequences in human DNA
AU - Gama-Sosa, Miguel A.
AU - Wang, Richard Y.H.
AU - Kuo, Kenneth C.
AU - Gehrke, Charles W.
AU - Ehrlich, Melanie
N1 - Funding Information:
ACKNOWLEDGEMENTS We are grateful to Drs. Monroe Samuels and Richard Harrison for providing us with various human organ and cell samples and to Dr. Joseph Maio for giving us the cloned Eco repeat sequence. We thank Mrs. Agnes Boyd for help with the manuscript. This study was supported in part by National Institutes of Health grant CA-19942.
PY - 1983/5/25
Y1 - 1983/5/25
N2 - Previously, we found much tissue-or cell-specificity in the levels of 5-methylcytosine (m5C) in the total human genome as well as in DNA fractions resolved by reaasociation kinetics. We now report that there were even greater differences in the m5C content of the highly repeated, tandem EcoRI family of DNA sequences from different human organs or cell populations. The ratio of m5C levels in this DNA fraction from brain, placenta, and sperm was 2.0:1.2:1.0. At a HhaI site in this repeat family, sperm DNA was 5-10 fold less methylated than somatic DNAs. In contrast, the highly repeated Alu family, which is 5 of the genome, had almost the same high m C content in brain and placenta despite marked tissue-specific differences in m C levels of the single copy sequences with which these repeats are interspersed. These data show that very different degrees of change in methylation levels of various highly repeated DNA sequences accompany differentiation
AB - Previously, we found much tissue-or cell-specificity in the levels of 5-methylcytosine (m5C) in the total human genome as well as in DNA fractions resolved by reaasociation kinetics. We now report that there were even greater differences in the m5C content of the highly repeated, tandem EcoRI family of DNA sequences from different human organs or cell populations. The ratio of m5C levels in this DNA fraction from brain, placenta, and sperm was 2.0:1.2:1.0. At a HhaI site in this repeat family, sperm DNA was 5-10 fold less methylated than somatic DNAs. In contrast, the highly repeated Alu family, which is 5 of the genome, had almost the same high m C content in brain and placenta despite marked tissue-specific differences in m C levels of the single copy sequences with which these repeats are interspersed. These data show that very different degrees of change in methylation levels of various highly repeated DNA sequences accompany differentiation
UR - http://www.scopus.com/inward/record.url?scp=0021111964&partnerID=8YFLogxK
U2 - 10.1093/nar/11.10.3087
DO - 10.1093/nar/11.10.3087
M3 - Article
C2 - 6856456
AN - SCOPUS:0021111964
SN - 0305-1048
VL - 11
SP - 3087
EP - 3095
JO - Nucleic Acids Research
JF - Nucleic Acids Research
IS - 10
ER -