Parasites and DNA?
Can parasites in humans be passed down through a family(genes/DNA)?
- dumbdumbLv 41 decade agoFavorite Answer
Hi, the answer seems to be "YES"!
I did a quick google search for "Parasitic DNA and Humans", and discovered this. Pretty interesting. The article includes remarks by other scientists expressing doubt over the findings, but I bet most scientists are not surprised. Please find the summary of findings below:
Invasive Genes: Humans incorporate DNA from parasite
The "us-against-them" mindset may take on new meaning when applied to infections by the parasitic protozoan Trypanosoma cruzi. New research shows that bits of foreign DNA from the parasite become integrated into the DNA of an infected person. This is the first time that parasitic DNA has been found in the human genome, says Antonio Teixeira of the University of Brasilia in Brazil.
DNA DONOR? A single parasite of the species Trypanosoma cruzi (center) swims among the blood cells of an infected person.
"This is a very new idea, and as such it will be controversial," says parasitologist David A. Campbell of the University of California, Los Angeles, who was not involved in the study. "It's surprising, but I'm convinced by the data."
More than 16 million people in South America are infected with T. cruzi, the causative agent of Chagas' disease, and 50,000 people die of the disease there each year. Most contract the chronic disease early in life with little serious effect at that time. Decades later, 30 percent of infected people suffer damage to vital organs, most notably the heart. Many other biological details of the disease remain a mystery.
Teixeira and his team analyzed the DNA of 13 adults with heart damage from Chagas' disease. The researchers found pieces of DNA from the parasite within the genome of each patient, primarily at a specific location on chromosome 11, the researchers report in the July 23 Cell.
A parasite's DNA is called kinetoplast-DNA (kDNA), and it's not normally present in multicellular organisms. "It pollutes the human genome," Teixeira says of T. cruzi's kDNA.
To confirm that kDNA can get into chromosomes, Teixeira turned to chickens, which don't naturally contract Chagas' disease. His team injected newly fertilized eggs with T. cruzi and found that about a quarter of them incorporated the kDNA into their own DNA. The scientists proved this by breeding kDNA-positive roosters and hens and then their offspring. All the offspring for two generations after the injections turned out positive for kDNA. Those chicks had to get kDNA from their parents' DNA, since they themselves were never infected with T. cruzi.
Although the chickens passed down kDNA to later generations, this doesn't mean people inherit Chagas. Most human infections generally occur in childhood, after the embryonic phase of development, which is when the chicks were infected.
It remain unclear how, and even whether, kDNA affects the course of Chagas' disease. To some scientists, the integration of parasite kDNA into a host's DNA fits in with an increasingly popular but hotly debated idea that the illness is partly an autoimmune disorder, in which a person's body attacks its own tissues. When human cells use the genes surrounding incorporated kDNA to make new proteins, the immune system may identify them as coming from the parasite and worthy of attack, speculates Teixeira.
Because kDNA could get into the DNA in many different types of tissues, it may explain why Chagas' disease affects many organs, says Teixeira.
Other scientists remain skeptical that genomic kDNA integration is even a real phenomenon. "It's a wild idea, and it's hard to imagine how it would happen," says immunologist Rick L. Tarleton of the University of Georgia in Athens. "One would want to see independent confirmation before accepting it."Source(s): Nitz, N. . . . and A.R.L. Teixeira. 2004. Heritable integration of kDNA minicircle sequences from Trypanosoma cruzi into the avian genome: Insights into human Chagas disease. Cell 118(July 23)175-186. Abstract available at http://www.cell.com/content/article/abstract?uid=P...
- 1 decade ago
Parasites such as worms and protozoans cannot be passed down through DNA. However, it seems plausible that an intracellular parasite could be passed from a parent to the child by occupying either the sperm or egg.
There are 'parasites' that are actually DNA sequences, and they make up most of our genome. They are called retrotransposons and they evolved from retroviruses. They are peices of DNA that can copy themselves and insert the copy into a new place in the genome. They 'reproduce' in this way - and are extremely numerous in humans and other mammals.
- 1 decade ago
no, unless that parasite alters the hosts DNA somehow, in which case only the traits of the altered DNA would pass on, not the parasite itself. However, depending on the method of transmission, it is possible for all members of a family to have the parasite through casual contact with each other.
- belfusLv 61 decade ago
in addition to viruses inserting themselves into the genome, there is another possibility.
mitochondria are theorized to have originally been parasitic organisms that somehow got incorporated into the cells of organisms. Mitochondria have their own DNA independent of the cell's own DNA, and they replicate intracellularly on their own, and indeed these mitochondira will get passed from mother to her offspring. some people think it's possible to trace back ancestry all the way back to prehistoric times using mitochondrial DNA since it doesn't vary like human DNA.
- How do you think about the answers? You can sign in to vote the answer.
- 1 decade ago
Parasites cannot be passed through dna however it is possible they will be passed through in other ways for example the amniotic fluid and almost everything thats transported through the umbilical cordSource(s): My extensive knowledge
- 1 decade ago
no it cant happen!
no parasite can enter a sperm or an egg cell!
even if virus enters in any of these these will not result into a zygote
not even HIV virus! Actually virus is not a parasite.
a parasite should b a living thing. bit its not yet decided that is virus living thing or non living thing lol
placental transefer of this virus is not known
only GENETICAL DISEASES pass down through family!
- Anonymous1 decade ago
Parasites cannot be passed through the blood system over generations. However, a virus - just as HIV and AIDS can, especially when a baby is born - and the blood is mixed between its mother (who may have HIV/AIDS).Source(s): Health Class 4 years ago...
- Jena IsleLv 71 decade ago
No, they cannot be passed this way. Parasites can only be transmitted through direct contact, some through muscles, blood, air, contaminated food and water and others through the skin.
- Anonymous1 decade ago
Panda is correct. Give him the 10 points. Some viruses can be passed from one generation to the next, by inserting themselves into the genome (lysogeny).
- Random PersonLv 41 decade ago