A New Tool for Conservation Genetics: Seal Placentas

When species become rarer, there is a small population of species that can pass their genes and many will start to inbreed. Inbreeding can cause a lack of genetic diversity, which can lead to birth defect and other negative effects. Inbreeding can cause an endangered species to be more endangered as time passes. The genetic makeup of endangered species are tested regularly by conservationists to understand the threats and at times help them breed. However, collecting DNA samples from an animal can be risky and harmful to the animal and the person collecting the DNA or there may not be enough of a sample to analyze the DNA fully.

Researchers from Finland found that placentas can be used to provide the maximum information of an animal when collecting DNA samples. The researchers studied the placentas of Saimaa ringed seals, where only about 300 of the seals remain in Finland. The researchers collected 59 placentas between 2009 and 2011 from the birthing dens of seals. Placenta testing revealed information about the pups’ genotype and exhibited low genetic diversity. The test could not reveal the genes of the mother and which pups were siblings. The study shown that placentas can be used in genetic monitoring.

This study can help save endangered species, which do not eat their placenta, by identifying any diseases it can have from a low breeding population. Also, the study can help conservationists decide if they need to introduce a species into the population to increase the gene pool and which species to use.

Original Link: http://blogs.scientificamerican.com/extinction-countdown/2015/04/17/genetics-seal-placentas/

Related Linked: http://www.nmfs.noaa.gov/pr/species/mammals/pinnipeds/saimaaseal.htm

Seal Placentas Aid in Conservation Efforts

A recent article in Scientific American discusses the new importance found in seal placentas. Recent research has displayed that seal placentas are very effective in genetic research, showing the amount of inbreeding and even the gender of the offspring. This method of collection allows conservationists to collect DNA samples easier, with no risk to themselves or the seals being studied.

Seals are being monitored for inbreeding due to the occurrence of a small gene pool. When an animal becomes endangered, a limited amount of breeding choices result in a much greater risk of inbreeding within the population. Scientists wish to observe inbreeding to gain a better understanding of the risks involved with extremely endangered species.


A group of Finnish researchers collected several placentas from the extremely rare Saimaa ringed seals. Material extracted from the side of the placenta attached to the uterine lining contained DNA from the mother, while the side connected to the fetus gave DNA from the offspring. The sample of collected placentas exhibited the expected low amount of genetic diversity.With only an estimated number of three hundred seals remaining in the wild, inbreeding becomes a very critical issue. Unfortunately, this collection technique can not be applied to most mammals because the vast majority exhibit placentophagia, or eating the placenta after the birthing process.