by How does nuclear radiation affect animals?
The Nuclear radiation It is a type of ionizing radiation that at certain thresholds is very harmful to animal cells and tissues. Ionizing radiation causes damage such as:
- Playback issues: the reproductive system is the most sensitive to radiation.
- Cancer: increased chance of developing cancer.
- Metabolic deficiencies: compounds released in nuclear leaks, such as iodine-131, affect the proper functioning of the thyroid gland.
- Immunosuppression: radiation reduces the number of lymphocytes.
- Blood infections: radiation reduces leukocytes and platelets.
- pneumonias: radiation causes damage to the alveolar barrier.
- Waterfalls: It causes damage to the maturation of the crystalline lens.
- Encephalopathies: it causes damage to the myelin sheaths of nerve cells and also vascular damage.
Where do the Chernobyl dogs come from?In 2017 a study group of the Chernobyl dogs In response to the increase in the population of feral dogs in the area where the tragedy occurred. This zone, known as the exclusion zone, has an extension of 2600 km2.
For two years, stray dogs from Chernobyl were provided with veterinary care. In addition they were taken blood samples to analyze your DNA.
Mutation Rate and Genetic Diversity in Animals
The mutations occur spontaneously in nature and are a natural mechanism that increases the genetic diversity of populations. The rate at which these mutations occur is called mutation rate.
Compounds released into the environment as a result of nuclear accidents such as Chernobylcan increase the mutation rate. A high mutation rate can result in health problems, such as the appearance of certain diseases such as cancer..
Conversely, when radiation causes fertility problems, genetic diversity could be reduced by reducing the number of breeding individuals.
What is the genetic structure of the Chernobyl dogs like?has been sequenced DNA from 302 Ukrainian dogs from three Chernobyl zones:
- Inside the power plant.
- 15 kilometers from the disaster site.
- 45 kilometers from the disaster site.
There is enough genetic differentiation to say that individuals from the power plant and the city of Chernobyl are genetically different. This implies two different populations.
Has the DNA of the Chernobyl dogs mutated as a result of radiation?
The study authors point out that Chernobyl populations have a unique genomic signature and propose that these populations are ideal for study and identify genomic loci associated with long-term radiation exposure.
However, Other experts affirm that the factor that has most affected the population structure of the Chernobyl dogs is not radiation, but the absence of human beings.. The Chernobyl dogs would have been isolated for more than 30 years, reproducing among themselves and without the contribution of genes from other domestic breeds. This would be the cause of the differences found between the stray dogs of Chernobyl and other stray dogs from another place.
They doubt, therefore, the use of these dogs as a model of affection of nuclear radiation in the genome. They further add that:
- In Chernobyl currently the radiation is similar to that of any other place. only one 1% of all Chernobyl are high and dangerous radiation zones. These zones are patchy around the nuclear complex.
- A dog that is moving you are never exposed 24 hours a day to high radiation.
- The work does not include any measurement of radiation only studies the genetic diversity of dogs in different areas of Chernobyl.
References:
- Nagasawa, M. et al. 2012. Continued distress among abandoned dogs in Fukushima. Sci. Rep. 2724.
- Spatola, G Jet al. 2023. The dogs of Chernobyl: Demographic insights into populations inhabiting the nuclear exclusion zone. Science Advances, 9(9), eade2537.
