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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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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
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Home | Pregnancy Timeline | News Alerts |News Archive Oct 29, 2014

“During pregnancy, a small number of fetal cells circulate around the mother’s body, and it seems that in some women, they persist as long as several decades." Giovanna Cruz MS, UC Berkeley


CDC Growth Standards 0 to 2 Years of Age


Kid’s genes and moms’ risk for rheumatoid arthritis

A child’s genetic makeup may contribute to his or her mom's risk of rheumatoid arthritis, possibly explaining why women are more at risk for developing the disease than men.

This research was presented Tuesday, October 21, at the American Society of Human Genetics (ASHG) 2014 Annual Meeting in San Diego.

Rheumatoid arthritis, a painful inflammatory condition that primarily affects the joints, has been tied to a variety of genetic and environmental factors, including lifestyle and previous infections.

Women are 3 times more likely to develop rheumatoid arthritis than men, peaking in their 40s and 50s.

Certain versions of the immune system gene HLA-DRB1 are associated with the condition. HLA genes are involved in the immune system’s response to infection and in transplant medicine, for differentiating between your own cells and those that are foreign.

The female bias for rheumatoid arthritis strongly suggests pregnancy is involved, according to Giovanna Cruz MS, graduate student at the University of California, Berkeley, and first author on the new study.

“During pregnancy, a small number of fetal cells circulate around the mother’s body, and it seems that in some women, they persist as long as several decades.

"Women with rheumatoid arthritis are more likely to have persistent fetal cells — fetal microchimerism — suggesting a potential risk factor for rheumatoid arthritis.

“We don't know why it happens, but we suspect HLA genes may be involved."

Giovanna Cruz MS, graduate student at the University of California, Berkeley

Researchers analyzed genes of women and their children for forms of HLA genes associated with rheumatoid arthritis. They found that having children with these high-risk genes – inherited from the child’s father – increased women’s risk for rheumatoid arthritis. These results verified that beyond a woman’s own genetic risk for the disease, there is additional risk by carrying and bearing children with high-risk genes.

“One possibility is that interactions between proteins these genes encode may stimulate autoimmune symptoms of the disease,” Ms. Cruz added. Therefore, a woman’s immune system may detect proteins produced by her fetus and mistakenly tag lingering fetal cells circulating through her blood stream as a threat. This would cause an immune reaction and symptoms of rheumatoid arthritis.

The findings may lead to new ways of assessing a woman’s risk for the disease depending on whether her children or partner carries the high-risk versions of genes. This is an area of research that Ms. Cruz and her colleagues are planning to explore.

Other future research includes genetically analyzing multiple generations of rheumatoid arthritis cases, including mothers of people with the disease, to further explore the role of HLA-encoded proteins and microchimerism.

Reference: Cruz G et al. (2014 Oct 21). Abstract: Increased risk of rheumatoid arthritis (RA) among shared epitope-negative (SE-) mothers with shared epitope-positive (SE+) children: Results from the Mother-Child Immunogenetic Study in Autoimmunity (MCIS). Presented at American Society of Human Genetics 2014 Annual Meeting. San Diego, Calif.

About the American Society of Human Genetics (ASHG)
Founded in 1948, the American Society of Human Genetics is the primary professional membership organization for human genetics specialists worldwide. Its nearly 8,000 members include researchers, academicians, clinicians, laboratory practice professionals, genetic counselors, nurses, and others with an interest in human genetics. The Society serves scientists, health professionals, and the public by providing forums to: (1) share research results through the ASHG Annual Meeting and in The American Journal of Human Genetics; (2) advance genetic research by advocating for research support; (3) educate current and future genetics professionals, health care providers, advocates, policymakers, educators, students, and the public about all aspects of human genetics; and (4) promote genetic services and support responsible social and scientific policies. For more information, visit: http://www.ashg.org.

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