mglater's blog

Many times throughout the day I took time to get food. Two large portions of time were taken out of my day in order to eat. The two times were rather different from each other. The first time was going to the Franklin Dining Commons, at which I received and ate breakfast. Later in the day, around noon, I was given free pizza before attending a meeting. Both of these portions of time took up roughly ten minutes each.

The ability to perform early, non-invasive prenatal tests such as the Harmony Test is due to the discovery of cell free fetal DNA (cffDNA). As the name implies, cell free DNA can be found free floating in the bloodstream. In the blood of a pregnant woman, both maternal cell free DNA and fetal cell free DNA can be found in the mother's blood. The fetal DNA comes from trophoblastic cells, the cells on the outer layer of a blastocyst. Some of these trophoblastic cells go through apoptosis (programmed cell death), and the DNA can end up in the mother’s bloodstream. The fetal DNA is present in the mother’s blood after five to seven weeks of gestation, and the amount of cffDNA present increases as the pregnancy continues. One challenge of studying the cffDNA is that the majority of the free DNA in the bloodstream is maternal, not fetal. In order to accurately assess the karyotype of the fetus, it must be possible to analyze the fetal DNA without any of the maternal DNA. The ratio of maternal cfDNA and fetal cfDNA can vary greatly between each individual, with some reports claiming 3-6% of the DNA being fetal and others claiming 11-13.4% being fetal. The major difference allowing for differentiation between the two sources of DNA is that fetal DNA segments are around 200 base pairs long, which is significantly shorter than the maternal DNA fragments. To collect the DNA, the blood sample from the mother is spun down in a centrifuge to separate out the plasma, from which the cffDNA can be isolated and purified via methods such as PCR or use of a mass spectrometer.

    Of course, the science and technology seen in the movie are works of fiction. In reality, while we are making great advances in the field of genetic testing, we are still nowhere near being able to do what is shown in the film. As discussed in class, prenatal genetic tests are rising in popularity, being used to detect certain genetic abnormalities. However, these tests are nowhere near the level of the tests in the film. We are able to detect large abnormalities such as a trisomy, but small things like controlling hair color, height, etc. are not able to be manipulated. In some cases, it is unclear which genes end up contributing to a certain trait. A lot of research into what DNA sequence causes certain traits would need to be performed before any test of that level could be reached.

The ability to perform early, non-invasive prenatal tests such as the Harmony Test is due to the discovery of cell free fetal DNA (cffDNA). As the name implies, cell free DNA can be found non-encapsulated in the bloodstream. In the blood of a pregnant woman, both maternal cell free DNA and fetal cell free DNA can be found. The fetal DNA comes from trophoblastic cells, the cells on the outer layer of a blastocyst. Some of these trophoblastic cells go through apoptosis, and the DNA can end up in the mother’s bloodstream. The fetal DNA is present in the mother’s blood after five to seven weeks of gestation, and the amount of cffDNA present increases as the pregnancy continues. One challenge of studying the cffDNA is that the majority of the free DNA in the bloodstream is from the mother. In order to accurately assess the karyotype of the fetus, it must be possible to analyze the fetal DNA without any of the maternal DNA. The ratio of maternal cfDNA and fetal cfDNA can vary greatly between each individual, with some reports claiming 3-6% of the DNA being fetal and others claiming 11-13.4% being fetal. The major difference allowing for differentiation between the two sources of DNA is that fetal DNA segments are around 200 base pairs long, which is significantly shorter than the maternal DNA fragments. The blood sample from the mother is spun down in a centrifuge to separate out the plasma, from which the cffDNA can be isolated and purified via methods such as PCR or use of a mass spectrometer.

    Both the Knapp paper and the Leppakoski paper begin with with an abstract. This tends to be true with nearly all scientific papers. The abstract is an overview of all of the sections of the report, giving the reader information quickly and allowing them to decide if they want to read the entire paper. Both papers then continue to the introduction section, where the background of the report is introduced. After this however, they begin to differ. The Leppakoski paper jumps immediately into results. The results section does not have an overarching header, but instead begins right after the introduction. The results are split into a few main categories, some of which are broken down further. The results are followed by a few paragraphs of discussion and conclusion, and the paper ends with acknowledgements and references.

The film Gattaca is an interesting look into a possible future if genetic testing were to continue advancing to an extreme level. The thought of genetic testing and manipulation reaching the level it has in the movie is both fascinating and terrifying. The movie does a good job of mentioning both the positives and the negatives of this extreme advance. It explains how the ability to easily create a baby of a specific genome would be an extremely useful means of preventing disease. Even at a more realistic level of genetic testing, closer to what may be achievable in upcoming years, the ability to detect extreme genetic abnormalities could lead to saving people from a lot of suffering. This type of screening could eliminate chromosomal abnormalities, as well as smaller problems such as sickle-cell anemia or another disease.

The specimen is roughly 30mm long and is a light brown color. There is a body (14mm) and a long narrow tail (16mm). The specimen is able to move by constricting and elongating its body, moving in a manner similar to a worm or caterpillar. When elongating, the length of the specimen increases by roughly 3mm. On the underside of the specimen there are eight small bumps, seemingly akin to feet. The creature only moves when these bumps are on the ground, supporting the belief that they function as feet. As the specimen crawls forward, the outer layer of flesh on the “head area” retracts, and two small protrusions are produced from the face. I hypothesize that these protrusions form the mouth of the creature. The creature seems to have knowledge of its surroundings, as it attempted to crawl out of the holding container multiple times. The specimen would also cease movement if the holding container was moved or disturbed. This is likely a survival mechanism where the creature senses danger from being moved, and freezes in the hopes of not being discovered.

Brown

~30 mm

Body can elongate

Able to move

Moves in worm/wave like manner

Body ~14 mm

Upon movement able to lengthen body by ~3 mm

No specific movement of tail, seems to serve no purpose

2 sets of 4 bumps under body akin to feet

Front and back end of body dark brown, middle of body lighter brown

“Head” portion can open up and produce “face”

    2 very small lines  produced, possible mouth?

Seems to have clear outer skin layer that stretches, while brown layer beneath moves

Able to turn itself over

Small dark brown dots on body and 2 on tail

Underside slightly pink coloration

Thin dark brown line running down center of tail

Tail has slight curve at very tip

Likely a larva/caterpillar of some sort

Unable to climb walls of container

    *was able to bring head over lip of container

Crawls around edge of container

Kept in sawdust

When disturbed, freezes in place for short time before resuming motion

Pieces of sawdust able to stick to face

    Unknown if intentional biting or simply sticking

Able to lift head portion into air

Tail somewhat flexible, able to get folded under body without breaking

Long period of time with no movement

    Later resumed moving

Possibly aware of confinement, multiple attempts to climb out

    Suggests some level of intelligence/awareness

What is it?

Can it see?

What does it eat?

Does it interact with other ones of whatever it is?