Genomic imprinting: the epigenetic battle of the sexes

This Valentine’s Day, satisfy your burning desire for something more than Mendelian genetics with Wendy Chao’s Genomic Imprinting: an epic saga of the epigenetic battle of the sexes. Genomic imprinting is a process that modifies gene expression based on the sex of the transmitting parent. Learn all the sensual, sordid details about this epigenetic phenomenon (and how it relates to asses, hinnies, ligers, and tigons) in Chapter 22 of Handbook of Epigenetics: The New Molecular and Medical Genetics, edited by Trygve O. Tollefsbol:

Handbook of Epigenetics: Chapter 22 Genomic Imprinting
Available now wherever books of this nature are sold!

Friends and colleagues: contact me about how to obtain a copy of the chapter for non-commercial purposes, such as research and/or educational use.


Chao W. Genomic Imprinting. In: Handbook of Epigenetics: The New Medical and Molecular Genetics. London: Elsevier/Academic Press, 2011, 353-379.

| ScienceDirect |

Related works:

Chao W, D’Amore PA. IGF2: epigenetic regulation and role in development and disease. Cytokine Growth Factor Rev. 2008 Apr;19(2):111-20.

| Google Scholar | PubMed |

Chao W, Huynh KD, Spencer RJ, Davidow LS, Lee JT. CTCF, a candidate trans-acting factor for X-inactivation choice. Science. 2002 Jan 11;295(5553):345-7.

| Google Scholar | PubMed |

Site restoration

The year 2010 marked the demise of this blog—partially due to the fact that I was running too many side projects (and a prehistoric version of WordPress that did not survive the database upgrade). An ongoing and painstaking restoration process will hopefully return this site to its former splendor. A thorough site makeover is also in order, as there are many outdated pages and links. Furthermore, the layout is, like, so 2002. Stay tuned!


Not enough time in the day for website AND Facebook, so Facebook wins…for now.

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I have a form of hypodontia, a condition of naturally missing one or more teeth. I don’t have any wisdom teeth:


no wisdom teeth!


This kind of hypodontia is pretty common, and is believed to be a product of natural selection in response to changes in human eating habits. It is also believed that the presence or absence of wisdom teeth depends on variation at the PAX9 gene locus, which regulates tooth development in humans and many other species. I think that’s very interesting – but everyone else is probably bored to tears.


Mensah JK, Ogawa T, Kapadia H, Cavender AC, D’Souza RN. Functional analysis of a mutation in PAX9 associated with familial tooth agenesis in humans. J Biol Chem. 2004 Feb 13;279(7):5924-33.

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Pereira TV, Salzano FM, Mostowska A, et al. Natural selection and molecular evolution in primate PAX9 gene, a major determinant of tooth development. Proc Natl Acad Sci USA. 2006. Apr 11;103(15):5676-81.

| PubMed |

AND…just when I’ve run out of blogworthy material, another unauthorized reproduction of the ski bunny photo surfaces:

ANNOUNCING THE WORLD’S FIRST ACTUAL SUPERVILLAIN: Ladies and gentlemen, I’m here to tell you a story. A story that may very well burrow into your soul and take up permanent residence; a chilling tale so unbelievable it would be incredible, if only it weren’t absolutely true. I talk of the arrival of the world’s first supervillain.” [CONTINUE READING at CRACKED.COM]


ski bunny


Unfortunately, I am not the “supervillain” in this article. Even more unfortunately, spellcheck was “aparrently” not used – and there’s no “aparrent” reason why this photo is associated with this story. Still, I’M ON FREAKIN’ CRACKED.COM!! This is truly an honor. Truly. In fact, this might be the coolest thing that has ever happened to me! This might offset the fact that I have duct tape on my glasses right now!


Sincere apologies about the lack of updates on the story of Buddy the caterpillar (who did turn into a beautiful Buddy-Fly). Photos & stories soon to follow. I’ve been pretty busy, but I wanted to write something because today is kind of a special day for me. Ten years ago on this day, I was almost killed in a bike-SUV collision. I had critical injuries – the hospital staff later confessed that they didn’t think I would survive – but here I am today. I am a little less coordinated than I used to be, I have quite a few scars, and still struggle with learning & memory problems – but I still think I am the luckiest girl alive. I have posted some images from that day, and the weeks that followed. The pictures aren’t too bad; maybe just a little bit sad. However, there’s a happy smiling picture of me at the end:

Special thanks to the doctors, family members, friends, and bike helmet that saved my life.