1. Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hwasun Hospital, 160 Ilsimri, Hwasun-eup, Hwasun-gun, Jeollanam-do 519-809, Republic of Korea
2. Brain Korea 21 Plus Project, Chonnam National University Medical School, Gwangju, Republic of Korea
3. Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
4. Environment Health Center for Childhood Leukemia and Cancer, Chonnam National University Hwasun Hospital, Hwasun, Republic of Korea