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Welcome to The Visible Embryo, a comprehensive educational resource on human development from conception to birth.

The Visible Embryo provides visual references for changes in fetal development throughout pregnancy and can be navigated via fetal development or maternal changes.

The National Institutes of Child Health and Human Development awarded Phase I and Phase II Small Business Innovative Research Grants to develop The Visible Embryo. Initally designed to evaluate the internet as a teaching tool for first year medical students, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than one million visitors each month.

Today, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than 1 million visitors each month. The field of early embryology has grown to include the identification of the stem cell as not only critical to organogenesis in the embryo, but equally critical to organ function and repair in the adult human. The identification and understanding of genetic malfunction, inflammatory responses, and the progression in chronic disease, begins with a grounding in primary cellular and systemic functions manifested in the study of the early embryo.

WHO International Clinical Trials Registry Platform

The World Health Organization (WHO) has created a new Web site to help researchers, doctors and
patients obtain reliable information on high-quality clinical trials. Now you can go to one website and search all registers to identify clinical trial research underway around the world!




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Disclaimer: The Visible Embryo web site is provided for your general information only. The information contained on this site should not be treated as a substitute for medical, legal or other professional advice. Neither is The Visible Embryo responsible or liable for the contents of any websites of third parties which are listed on this site.
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Pregnancy Timeline by SemestersFetal liver is producing blood cellsHead may position into pelvisBrain convolutions beginFull TermWhite fat begins to be madeWhite fat begins to be madeHead may position into pelvisImmune system beginningImmune system beginningPeriod of rapid brain growthBrain convolutions beginLungs begin to produce surfactantSensory brain waves begin to activateSensory brain waves begin to activateInner Ear Bones HardenBone marrow starts making blood cellsBone marrow starts making blood cellsBrown fat surrounds lymphatic systemFetal sexual organs visibleFinger and toe prints appearFinger and toe prints appearHeartbeat can be detectedHeartbeat can be detectedBasic Brain Structure in PlaceThe Appearance of SomitesFirst Detectable Brain WavesA Four Chambered HeartBeginning Cerebral HemispheresFemale Reproductive SystemEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterSecond TrimesterFirst TrimesterFertilizationDevelopmental Timeline
CLICK ON weeks 0 - 40 and follow along every 2 weeks of fetal development
Google Search artcles published since 2007

Home | Pregnancy Timeline | News Alerts |News Archive Oct 7, 2014

Image credit: University of California San Diego



WHO Child Growth Charts




How to place a chemical tag to control a gene

Biochemists have developed a program that predicts where to place chemical tags to control gene activity.

The epigenome guides the development of all complex organisms from their beginnings as single fertilized eggs. Researchers analyzed epigenomic patterns in human embryonic stem cells (ESCs) and four cell lines derived from ESCs in order to create a catalogue of genetic elements that shape the epigenome as an embryo developes into an adult.

Damage to the epigenome not only disrupts infant development, but can happen at any point in our lives and lead to illness.

By editing DNA sequences that control epigenome modifications, scientists begin to understand how each guide functions and perhaps, in the future, may be able to mend epigenomic mistakes that cause harm.

By comparing sequences with and without epigenome modifications, the researchers identified DNA patterns associated with change. They called their program Epigram and have made both the program and the DNA motifs they have identified openly available to other scientists.

Their results are published in Nature Methods.

"All of our cells have the same blueprint – the same DNA – although they serve separate functions. Skin cells protect us, nerve cells send signals, and differences emerge when different subsets of genes are active or silent within particular groups of cells."

John Whitaker, lead author on the report.

These patterns of activity are controlled by modifying DNA, but not altering its sequence—chemical tags can influence which genes are read and which are skipped within a particular cell.

"The interplay between genetic and epigenomic regulation has only begun to be deciphered. This study revealed that there are specific DNA sequences that are recognized by DNA-binding proteins, which specify exactly where other enzymes place epigenomic marks."

Wei Wang, professor of chemistry and biochemistry who directed the work.

The epigenome is established and maintained by the site-specific recruitment of chromatin-modifying enzymes and their cofactors. Identifying the cis elements that regulate epigenomic modification is critical for understanding the regulatory mechanisms that control gene expression patterns. We present Epigram, an analysis pipeline that predicts histone modification and DNA methylation patterns from DNA motifs. The identified cis elements represent interactions with the site-specific DNA-binding factors that establish and maintain epigenomic modifications. We cataloged the cis elements in embryonic stem cells and four derived lineages and found numerous motifs that have location preference, such as at the center of H3K27ac or at the edges of H3K4me3 and H3K9me3, which provides mechanistic insight about the shaping of the epigenome. The Epigram pipeline and predictive motifs are at http://wanglab.ucsd.edu/star/epigram/.

Additional author Zhao Chen is a postdoctoral researcher working with Wang. John Whitaker, a former postdoctoral researcher in the group now works for Janssen Pharmaceutical Companies of Johnson & Johnson. A grant from the National Institute of Environmental Health Sciences to the San Diego Epigenome Center partially supported this work.

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