Dr. Roizen is a clinician scientist at the Children’s Hospital of Philadelphia.
His clinical interests include metabolic bone diseases with a focus on vitamin D metabolism, hyperparathyroidism and pseudohypoparathyroidism as well as obesity, type 2 diabetes and type 1 diabetes.
Dr. Roizen collaborates with Dr. Levine and Dr. Hakonarson. Each of whom has an active laboratory research program that complements and extends his clinical studies.
Dr. Roizen has more than 30 papers, patents and chapters.
He is a member of numerous professional societies, including the American Society for Bone and Mineral Research, the Endocrine Society, the Pediatric Endocrine Society and the American Diabetes Association. He is on the Editorial Board of the journal of Clinical Endocrinology and Metabolism (JCEM). He is a Fellow of the American Academy of Pediatrics.
Dr. Roizen is a 5.0-5.5 level competitive squash player and is a past champion of the St. Louis Open Amateur Draw and past runner up in the Windy City Open Amateur Draw. He is currently ranked in the top 500 nationally in the 5.0 skill group.
The goal of our laboratory is to understand non-calciometabolic effects of vitamin D and to use this understanding to design new therapeutic approaches to common diseases such as sarcopenia and obesity. Towards this goal we employ a uniquely diverse toolbox of methods using large human data sets and mouse physiology combined with high throughput sequencing to drive questions in cell culture and results from unbiased screening in cell culture to drive test-of-principle experiments and trials in mice and humans. Additionally, we rely on core principles of improv (“LISTEN” (to your collagues and to the data), say “yes, and…” (if you encounter a fact that doesn’t fit your theory, follow the fact), “find the game” (what is interesting, can you set up your Qs so that any answer is interesting), “If this is true, then what else is true…” (if you find something interesting, does it imply other interesting things), “there are no mistakes” (for well designed experiments, there are no failures)) to drive our science.
Qu HQ, Qu J, Glessner J, Liu Y, Mentch F, Chang X, March M, Li J, Roizen JD, Connolly JJ, Sleiman P, Hakonarson H.: Improved genetic risk scoring algorithm for type 1 diabetes prediction. Pediatr Diabetes May 2022.
Qu J, Qu HQ, Bradfield JP, Glessner JT, Chang X, Tian L, March M, Connolly JJ, Roizen JD, Sleiman PMA, Hakonarson H.: Insights into non-autoimmune type 1 diabetes with 13 novel loci in low polygenic risk score patients. Sci Rep 11: 16013, Aug 2021.
Mancilla EE, Zielonka B, Roizen JD, Dodds KM, Rand EB, Heimall JR, Chen F, Wu C, Goldberg DJ, Rychik J.: Growth in Children with a Fontan Circulation. J Pediatr Aug 2021.
Qu HQ, Qu J, Bradfield J, Marchand L, Glessner J, Chang X, March M, Li J, Connolly JJ, Roizen JD, Sleiman P, Polychronakos C, Hakonarson H.: Genetic architecture of type 1 diabetes with low genetic risk score informed by 41 unreported loci. Commun Biol 4: 908, Jul 2021.
Qu HQ, Qu J, Bradfield J, Glessner J, Chang X, March M, Mentch FD, Roizen JD, Connolly JJ, Sleiman P, Hakonarson H.: Combined Application of Genetic and Polygenic Risk Score for Type 1 Diabetes Risk Prediction. Diabetes Obes Metab May 2021.
Qu J, Qu HQ, Bradfield JP, Glessner JT, Chang X, Tian L, March ME, Roizen JD, Sleiman PM, Hakonarson H.: Association of DLL1 with type 1 diabetes in patients characterized by low polygenic risk score. Metabolism 114: 154418, Jan 2021.
Casella A, Long C, Zhou J, Lai M, O'Lear L, Caplan I, Levine MA, Roizen JD.: Differential Frequency of CYP2R1 Variants Across Populations Reveals Pathway Selection for Vitamin D Homeostasis. J Clin Endocrinol Metab 105: 1302-15, May 2020.
Roizen JD, Asada M, Tong M, Tai HH, Muglia LJ.: Early pregnancy loss in 15-hydroxyprostaglandin dehydrogenase knockout (15-HPGD(-/-)) mice due to requirement for embryo 15-HPGD activity. Sci Rep 9: 17612, Nov 2019.
Roizen JD, Levine MA: Response to: Obesity and Vitamin D Metabolism Modifications. Journal of bone and mineral research 34(7): 1384, Jul 2019.
Roizen JD, Long C, Casella A, O'Lear L, Caplan I, Lai M, Sasson I, Singh R, Makowski AJ, Simmons R, Levine M: Obesity Decreases Hepatic 25-Hydroxylase Activity Causing Low Serum 25-Hydroxyvitamin D. Journal of bone and mineral research 34(6): 1068-1073, Jun 2019.
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Last updated: 10/16/2022
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