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Genetic Mapping: Chimps vs. Humans
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When genome of the species is completely sequenced, gene mapping is used to graphically show where each gene is located on the chromosome. Restriction enzymes are used to slice DNA into fragments that are further separated by electrophoresis. DNA migration on the gel is known as DNA fingerprinting.

We share the same ancestor and genetic differences between human and animals are not as big as we thought they’ll be. Just couple percent of differences in DNA material is what makes us totally different from chimpanzees – our closest cousins. Bonobos are coming right after them. Our last known mutual ancestor lived six million years ago, when divergent evolution began (and modern human start developing). Chimps and bonobos start their separate evolution some million years ago. Clint was the first chimp whose genome was sequenced. He died at age 25 but info provided by his DNA made him immortal. Once chimp genetic map was clearly present, serious investigations on differences between two genomes started.

How different our genomes actually are? Single nucleotide difference exist in 1,2% of chimp’s genome . 3% of differences are result of deletion or insertion of certain parts of DNA and 2,7% of differences are result of gene duplication. DNA variations are result of “parasitic” DNA particles (acting like viruses) that were also inherited from our mutual ancestor. They are making duplicates of themselves that could be inserted in other part of the genome, but they are also responsible for deleting some of our genes and creating some new ones (by inserting and combining parts of functional genes…). All together, 50% of our genome is not associated with proteins vital for our survival which are result of long evolution where DNA material changed both its quality as quantity. Parasitic particles are present in both chimp and human genome, but they are more active in human genome inducing bigger genetic changes.

What makes us human? Mutations are affecting every genome, leading to gene silencing or can result in novel characteristic development. Newly created genes will be passed to the next generation if they are useful for survival. What inevitably separated us from chimpanzees and made us what we are today is associated with changes happened in our brains. Genes associated with brain functioning and development have undergone mutations that were helpful and thus highly appreciated in everyday life. Modified genes start transferring to the next generation and soon differences between humans and chimps became so huge that it was hard to believe that just “few” years of evolution took us away from our mutual ancestor.

Possibly biggest differences between human and chimps can be seen in Y chromosome (~30%). SRY gene is located in the Y chromosome and his expression will trigger embryonic development as male. Y is lot smaller than other sex chromosome (X) which is main obstacle for exchange of genetic material during meiosis (recombination is not possible due to “asymmetry” in their sizes). Genes on the Y are beneficial for male and they are well preserved, but some other parts are lost (not being useful in evolution) leading to shrinking of the chromosome. Chimps lost even bigger parts of their Y chromosomes and some scientists believe that reason for this evolutionary change might lie in their promiscuous behavior. When female is in oestrus, she is mating with more than one male. Selective pressure to produce more sperm and to be successful in fertilizing egg, will eventually led to transferring “superior” sperm genes to the next generation as those characteristic will have more advantage than other genetic characteristics linked to the Y chromosome. Human doesn’t have to compete so heavily for females, so our Y chromosome evolution didn’t happened so rapidly.

Most scientists consider medical related differences between chimps and humans most important for further investigation. We can be more resistant to some diseases that chimps are highly prone to (like sleeping sickness) and vice versa (chimps don’t develop Alzheimer disease for example). What differences in our genetic material is making us resistant or prone to some medical condition? This question is very important because solving the “resistant” genes mysteries would enable us to find a cure for some serious medical conditions that human and chimp populations are facing today.
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Genetic Mapping: Chimps vs. Humans00