- DNA stands for “deoxyribonucleic acid.”
- DNA is the hereditary substance that humans and most other organisms carry.
- The molecules which are building blocks of DNA are called nucleotides.
- The actual length of human DNA is approximately 3 metres.
- German biochemist Frederich Miescher discovered DNA in 1869.
- As nitrogenous bases, nucleotides are made from either ribose sugar (RNAs) or deoxyribose sugar (DNAs).
- DNA nitrogen bases have 4 types: adenine (A), thymine (T), guanine (G) and cytosine (C).
- One strand’s head lays against another strand’s tail, meaning that all two strands of DNA are antiparallel.
- The human genome contains 3 billion base pairs of DNA.
- Only about 3% of the total DNA are genes.
- DNA is a cell’s largest biomolecule/macromolecule.
- DNA molecules are so long that they are coiled tightly into structures called chromosomes for them to fit inside cells.
- The genome refers to the haploid set which is half the total number of chromosomes in an organism.
- A human cell contains 23 pairs equal to 46 chromosomes. There are 23 chromosomes in the human genome.
- The haploid cells in the human body are only the egg and sperm cells.
- Humans share 99% of identical DNA; only 1% contains each one’s unique identity.
- Red blood cells spring from DNA, but they are the only cells in the body that do not contain DNA.
- Humans share 60% DNA with bananas.
- Humans share 98% DNA with chimpanzees, while 50% is identical to that of a garden cabbage.
- The human genome’s complete sequence would take almost 50 years to type at a speed of 60 words per minute at 8 hours a day.
Understanding DNA could go a long way, from winning justice in court cases to the innovation of specialised medications. In other words, knowledge of the human genome benefits the legal, medical and social aspects of society. These DNA facts are just a few that are worth learning.
DNA replication is semiconservative.
As proven by scientists Franklin Stahl and Matthew Mesels, both DNA strands undergo independent replication. This process incorporates an original strand with a newly replicated one, hence making it a semiconservative DNA replication.
Oswald Avery discovered the genetic blueprint of humans in DNA in the 1940s.
Following this discovery by Avery, Francis Crick and James Watson discovered of the double-helix structure of DNA in 1953. Two long spiraling strands attached together by nucleotides comprised this structure.
DNA knowledge became a threat due to the possibility of creating “designer babies.”
The genome research raised concerns that such activity could not only edit out genetic imperfections but could also equip parents with choices on a child’s attributes. These modifications could range from eye and hair colour to intelligence level.
Identical twins have the same genetic code.
However, lifestyle and environmental factors present significant roles in their gene expression. It means that they could look distinctively the same, but they could also have indistinct differences. Scientists developed a test that detect such differences in 2015.
DNA in the cells of the body could stretch up to 10 billion miles when uncoiled.
A human cell contains crammed DNA which is about 2-3 metres long each. Its length when unwinded could cover a round trip to Pluto.
Sugar molecules, phosphate, and nitrogenous bases make up the ladder-like double helix structure of DNA.
While the bases make up the “rungs” of the ladder, sugar and phosphate molecules form the sides.
DNA has five types.
The most common type is the B-DNA, the rest are the A-DNA, C-DNA, D-DNA, and Z-DNA.
The only DNA type that is left-handed is the Z-DNA.
It indicates the direction to which the DNA strand is coiling.
The two DNA strands play roles in the regulation of heredity and metabolism.
The process involve both the sense and anti-sense strands. However, only the anti-sense or the “coding strand” serves as an RNA synthesis template.
The human genome contains about 8% of junk DNA.
It includes lingering strings of the viral genome that come from the same microorganisms which used to infect ancestors. In other words, the viruses that once affected relatives now dwells in your DNA. Thus, hereditary diseases.
A single gram of DNA could hold up to 700 terabytes’ worth of data.
It might as well be a better storage drive compared to any tech store’s hard drive. In comparison to the 2012 Harvard research, the Panama Papers only calculated a total of 2.6 terabytes.
Based on molecular structure, DNA nucleotides could be classified as either Purines or Pyrimidines.
Under purine structures as adenine and thymine, sporting double-ringed molecular structures. On the other hand, guanine and cytosine under pyrimidine structures only have single-ringed molecular structures.
DNA molecules are so fragile that they could be damaged easily.
It could create changes in the entire gene sequence for reasons such as cell damage due to UV light overexposure and common errors in genetic transcription. Some of the damages on genes could not be undone or repaired. On the other hand, “mutations” last and could even be passed down to multiple generations.
DNA cells undergo damages more than a hundred times a day.
Even so, human bodies are equipped with able systems for repair mechanisms.
Scientists were only able to complete the first draft map of the human genome in 2000.
The collaboration of two rival scientist groups resulted in an amazing innovation that could reform medicine. Doctors could utilize it to deliver diagnoses and prescribe treatments that are specially tailored to the needs of each patient.
They completed the sequence in 2003.
It is a task far from easy and simple, but scientists from the Human Genome Project successfully deciphered the entire sequence 3 years following its first draft. This success paved the way for the possibility of explaining a similarity in the genes of human beings or other model organisms.
DNA testing was first used in criminal cases in 1985.
The first to experience its justice was Tommie Lee Andrews, a rapist from Florida in 1987. Following that is a serial killer from Virginia in 1988.
Not all DNA-incorporated genes are alike or functional.
Based on a molecular anatomy study, a gene has Cistron, Muton, and Recon. Cistron refers to the function of a gene. Muton is a unit of measurement of mutation and is the smallest unit change in a nucleotide pair. Recon works its wonders during the recombination of a gene and the cross-over through cell multiplication.
Forensic DNA is not fully foolproof.
DNA samples could be corrupted and deteriorate over time, and scientists could make errors in examining and interpreting procedures. A recent discovery even showed that genetic markers are not as unique as genetic makeups are. Hence, anyone from a sibling down to a total stranger could be wrongly convicted.
The International Space Station obtained DNA samples in 2008 from famous people.
They stored the samples on the “Immortality Drive” memory device and sent them into space to be kept at the Station. These copies, including that of Lance Armstrong and Stephen Hawking, are instruments to the goal of resurrecting humanity in case of apocalyptic devastation of the planet.
It is possible to have two sets of DNA within a body.
Known as “chimera,” this occurrence happens through the merging of multiple fertilised eggs during embryogenesis, or as a result of an organ or bone marrow transplant. One example is the “Two-Faced Cat” named Venus who had different sets of genes on each side of her body since birth.
Absorbing one’s own twin in the womb is another chimera possibility.
In 2002, Lydia Fairchild’s DNA test betrayed her, showing how she was not the mother of the children she bore. Further analyses then exposed the two sets of genes that she was carrying.
Genetic material could be used in the production of genetically transformed plants and microbes.
Cue in Genetic Engineering sciences, wherein recombinant DNA (rDNA) technology is used in the alteration of an organism’s genetic makeup.
A scientist organisation inscribed the lyrics of “It’s a Small World After All” into a bacterial genome.
Their objective was to develop a method to transmit messages for future forms of intelligent life.
The first successful cloning of an animal was on a tadpole back in the 1950s.
However, the one to become the most famous cloned animal was Dolly, a sheep (1996-2003).
Male humans used to have spikes on their penises.
It is the same case for felines, hyenas, bats, and a few primates. Thankfully, the genetic code of the “penile spine enhancer” vanished from human DNA around 700,000 years ago. Scientists believed that the probable cause is the widespread progression of monogamy.
The genetic similarities of cheetahs go as far as to have almost zero distinction among many cats’ DNA.
Due to an ice age 10,000 years back, the entire population of cheetahs got wiped out, leaving today’s generation profoundly inbred. Hence, only a few are able to deliver healthy offspring. Leopards, on the other hand, have fixed spots that they could not change.
The octopus could naturally edit its own genes.
It is very unlikely for humans, but scientists were able to develop CRISPR-Cas9, a complex tool with a protein base. This mechanism could alter a defective embryo’s DNA, leading to the prevention of inherited diseases.
Japanese, South Korean and Russian scientists are operating attempts to revive the woolly mammoth.
Aside from trying to resurrect extinct animals, scientists have also initiated diverse projects to clone living animals like cats, monkeys, and the endangered white rhinoceros.
Twice the gene count of a fly or worm is enough to make a human being.
A plant thale cress carries 26,000 genes, a nematode worm has 18,000, a fruitfly holds 13,000, yeast contains 6,000 while a tuberculosis microbe brings 4,000.