Title |
Folate deficiency causes uracil misincorporation into human DNA and chromosome breakage: Implications for cancer and neuronal damage
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Published in |
Proceedings of the National Academy of Sciences of the United States of America, April 1997
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DOI | 10.1073/pnas.94.7.3290 |
Pubmed ID | |
Authors |
Benjamin C. Blount, Matthew M. Mack, Carol M. Wehr, James T. MacGregor, Robert A. Hiatt, Gene Wang, Sunitha N. Wickramasinghe, Richard B. Everson, Bruce N. Ames |
Abstract |
Folate deficiency causes massive incorporation of uracil into human DNA (4 million per cell) and chromosome breaks. The likely mechanism is the deficient methylation of dUMP to dTMP and subsequent incorporation of uracil into DNA by DNA polymerase. During repair of uracil in DNA, transient nicks are formed; two opposing nicks could lead to chromosome breaks. Both high DNA uracil levels and elevated micronucleus frequency (a measure of chromosome breaks) are reversed by folate administration. A significant proportion of the U.S. population has low folate levels, in the range associated with elevated uracil misincorporation and chromosome breaks. Such breaks could contribute to the increased risk of cancer and cognitive defects associated with folate deficiency in humans. |
X Demographics
Geographical breakdown
Country | Count | As % |
---|---|---|
United States | 3 | 18% |
Japan | 1 | 6% |
France | 1 | 6% |
United Kingdom | 1 | 6% |
Unknown | 11 | 65% |
Demographic breakdown
Type | Count | As % |
---|---|---|
Members of the public | 10 | 59% |
Scientists | 5 | 29% |
Practitioners (doctors, other healthcare professionals) | 2 | 12% |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
United States | 6 | 2% |
United Kingdom | 2 | <1% |
Italy | 1 | <1% |
India | 1 | <1% |
Colombia | 1 | <1% |
Canada | 1 | <1% |
Hungary | 1 | <1% |
Russia | 1 | <1% |
Mexico | 1 | <1% |
Other | 0 | 0% |
Unknown | 326 | 96% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Student > Ph. D. Student | 77 | 23% |
Student > Master | 46 | 13% |
Researcher | 42 | 12% |
Student > Bachelor | 42 | 12% |
Student > Postgraduate | 19 | 6% |
Other | 59 | 17% |
Unknown | 56 | 16% |
Readers by discipline | Count | As % |
---|---|---|
Agricultural and Biological Sciences | 99 | 29% |
Biochemistry, Genetics and Molecular Biology | 68 | 20% |
Medicine and Dentistry | 57 | 17% |
Chemistry | 12 | 4% |
Nursing and Health Professions | 9 | 3% |
Other | 35 | 10% |
Unknown | 61 | 18% |