(electronic tone beeping) my name is kondwani phiri. i'm a genetic researcher. you could say, it's in my blood.

from an early age of about eight or nine or so, i had just a natural curiosity for the natural world. cancer runs in my family. in fact, i lost my aunt to breast cancer. and that peaked my interests in genetics. i'm fascinated by how the genes we inherit shape our biological destiny, including our health. i believe the key to treatments and cures for diseases like these, lies in explicit efforts to engineer human genes. but can we fix not only what's broken but also enhance our genetic codes and improve on mother nature?

the unique sequence of these base pairs are instructions for the body to make proteins. the base pairs are like musical notes on a score that tell a musician how to play a song. when all the different sections of the dna are played, the result is a biological symphony. (upbeat orchestral music) but like the musical note played out of key that compromises the entire performance, there is an error in one of annabel's genes. (annabel groans) (tense electronic music) the mutation in the atp1a3 gene is disrupting her nerve cells, leading to her severe condition. ahc is fundamentally intertwined in her genetic code. there is no restorative treatment or cure. - the medicines that they have are kind of more about masking symptoms in a very unspecific un-targeted way.

- and we wanted to try to figure out if there was a way to address the cause and not the symptoms. - [kondwani] without targeted treatment, annabel could die. any day. - [family] happy birthday, dear annabel. - there's a timeline on this for us. we've got a ticking cloak in the back of our minds, all the time. - the frosts are desperate for any kind of help. from sickle cell anea to huntington's disease, millions of people suffer from thousands of genetic disorders, much like annabel. unless scientists can address these genetic errors, children, like annabel, will suffer agonizing pain and some will die young. i want to know, can genetic engineering help families like this in the future? oh, good girl. - oh, that's so nice. (pensive electronic music) - the double helix structure in dna was first revealed in 1953 by rosalind franklin, francis crick and james watson,

and within a few decades, scientists discovered how to alter the dna of living organisms. but gene editing really took off around 2013 when scientists harnessed a molecular mechanism found in certain bacteria. this remarkable mechanism is called crispr-cas9 or crispr for short. crispr-cas9 contains an enzyme that serves as the bacteria's defense mechanism against viruses. when viruses infect the bacteria, the crispr machinery targets the specific section of dna. then the enzyme responds like a pair of scissors and literally cuts the virus's genetic code apart. scientists are now are harnessing this natural mechanism to target and precisely edit dna of numerous organisms.

(eerie dramatic music) - [kondwani] next, we insert crispr construct that will alter their dna. - we're gonna add in the crispr machinery and then change the cells. - [kondwan ah! the crispr machinery targets and edits a specific gene in the e. coli, so that they can adapt to a lethal dose of antibiotics. normally, bacteria can't grow in the presence of this antibiotic. the drug kills the bacteria. - we need to get these bacteria onto this plate, so they can grow. you're just gonna gently drag it across the surface of the plate. - that's it? - yeah, that's it. - [kondwani] over the course of several days, beth grows the gene edited bacteria in a petri dish laced with e. coli killing antibiotic.

but despite this toxic onslaught, thgenetically altered e. coli contue to grow.

to their environment survive and reproduce passing along their advantageous genetic traits to their offspring. these traits like heights, eye color, strength, and even personality are contained in genes. over generations, the process of natural selection perpetually fine tunes the species at the genetic level,

helping the individuals to continually adapt to changes in their environment. humans learned to direct this evolutionary process through artificial selection. through the intentional selection of mates, humans facilitated the breeding of animal offspring

theal crispr through the intentional mechanism in bacteria, and his use of crispr as a technology in milk is leading to remarkable innovations in dairy proteins. - so what we're looking at here is milk that is in the process of fermenting.

- [kondwani] okay, so this is in the earlier stage of things. - very early stage. so we add the bacteria to start the fermentation process and then used the lactose to solidify milk

at nc state's plants and microbial biology lab, rodolphe's colleague, mary beth dallas, is facing this daunting prospect. - i manage this lab and i also do research on cassava. - [kondwani] also known as the yuca plant, cassava is the primary food staple

collectively take in the excess carbon dioxide from the atmosphere, cooling the climate, and restoring balance to the world's ecosystem. (dramatic electronic music) - as i see it, gene editing is both a faster and more precise method for artificial selection. while it works in microbes and plants, how feasible is gene editing in our biologically complex organisms, like animals? i'm in davis, california to meet geneticist, alison van eenennaam. she's a pioneer in this fid. now i'm getting acquainted with her work. (cattle snorts) oh, no! - scientists tend to be problem solvers and wanna try and address problems using the best method they can,

and my lab is trying to breed better cattle. - [kondwani] there are about 1 billion cattle on earth. that's a lot of animals to manage, but allison is making cattle farms safer

ant d animal breeders, is disease resistance. and so globally, it's estimated we lose about 20% of all animal production to disease. - that's a large percent. that's hundreds of millions of cattle needlessly lost every year.

- to me, genetics is the best approach to deal with disease. 'cause if they don't get sick, they don't need to be treated with antibiotics. they're more productive. farmers hay. cattle are happy. consumers are happy. so it's kind of a triple win for stainability. - [kondwani] but there's an even more fundamental trait that allison is trying to select for. - in the beef cattle industry, we would actually prefer males. - [kondwani] that's because male beef cattle produce quantitatively more meat, per pound ofeed, thafemale. so allison is also usingene editing to breed cattle who only produce male offspring. to achieve this, she inserts a special gene in cow embryos in thlab. this makes selecting the male sex possible. this could save more animals from being slaughtered, and techniques like these could be used to insert disease resistance. potentially, reducing the need for antibiotics. in fact, a gene edited embryo was implanted into this cow just three months ago. - [alison] and there's princess.

- so in a few short moments, we're about to see an ultrasound of a cow here.

artificially selecting for the male sex could make cattle production more humane and more efficient. - there are some pretty compelling benefits that outweigh the risks. - [kondwani] seeing the genetitic engineering with livestock, up close and personal, is absolutely mind-blowing. (dramatic electronic music) - [narrator] in the future, engineering the genes of farm animals

speeds up their evolution as useful domestic species. the new variety cow, gene edited to dramatically reduce the emission of the climate damaging gas, methane, is vastly reducing global warming. organs from genetically modified pigs are safelymplanted into humans without fear of rejection from the immune system. no one dies from a lack of an organ donor anymore. (upbeat electronic music) - [kondwani] humans have selectively bred plants and animals, defining their traits for thousands of years. we've even created hybrids by making creatures from two different specie for example, a donkey and a horse make a mule. but in the lab, mixing up genetics can result in anything and, well, everything. jellyfish dna spliced into a bunny, results in a fluorescent bunny. when spider dna is edited into goats, their milk c be spun into spiderwebs.

hybrids like these are often bio-engineered for research purposes. but one scientist is using crispr's crossbreeding ability to do something truly ambitious. he's bringing back the genes of extinct species. i'm in cambridge, massachusetts to meet dr. george church. a legend in the field of genetics. one of the originators of gene engineering. he's been working in russian siberia, to find the remains of wooly mammoths, with the aim of resurrecting their dna to fight climate change. - there's unfortunately lots of melting ice in siberia and so there are millions of mammoths that are frozen, that are becoming exposed. we had access to six, really excellently frozen specimens. they had never thawed in 40,000 years. - when you were grabbing the samples- - ah. - from the wooly mammoth, anatomically, where? - [george] we're dissecting big chunks of mammoth legs with a drill bit and we're kind of suited up because there's meat flying all over the place.

(dramatic music) - [kondwani] due to over-hunting and environmental changes, wooly mammoths began going extinct around 10,000 years ago but george is extracting their dna from the cold preserved remains in siberia and mapping their genome. - once we read the genome into the computer and then we write it into modern asian elephant cells. - [kondwani] modn asian elephants and wooly mammoths share common ancestry, but are two distinct species. george is using advanced crispr techniques to resurrect multiple cold resistant genes from the wooly mammoth that grows their hair and produce more fat. he then plans to integrate these genetic traits into the eggs of asian elephants. - we can make dozens of edits to the genome and then clone them into baby elephants. - [kondwani] but why? it turns out cold resistant elephants could also help mitigate global warming.

eracted dna it turns out cold resistant elephants from dinosaur remains and are on the brink of resurrectinthese extinct species. the hope is by bringing a single dinosaur back to life, new technologies will be developed to help other species on the brink of extinction. (staccato electronic music) - [kondwani] speaking with george church, firsthand, is both humbling and inspiring. as if resurrecting the dna of the wooly mammoth wasn't enough, he also helped start a3 billion human genome project this landmark study identified every base pair of dna