Curious About DNA

PODCAST 203: CURIOUS ABOUT DNA

RELEASE DATE: SUNDAY, AUGUST 21ST, 2022

D:  HELLO, AND WELCOME BACK TO THE CURIOUS KID PODCAST.  HAVE YOU EVER WONDERED WHAT MAKES YOU YOU?  IN OTHER WORDS, WHAT IS IT THAT GIVES YOU THE TRAITS THAT MAKES YOU UNIQUE?

O:  I HAVE BROWN HAIR AND BROWN EYES, AND I ALSO HAVE FAIR SKIN, BUT WHY?  WHY DON’T I LOOK DIFFERENT THAN I DO?  I MEAN, I’M HAPPY WE ALL LOOK DIFFERENT, BECAUSE IT WOULD BE SO BORING AND CONFUSING IF EVERYONE LOOKED THE SAME, AND THE THINGS THAT MAKE ALL OF US DIFFERENT ALSO MAKE ALL OF US BEAUTIFUL.

D:  WELL, IT TURNS OUT THAT YOUR BODY HAS AN INSTRUCTION MANUAL THAT IT USES TO MAKE YOU THE PERSON THAT YOU ARE.  EACH OF OUR BODIES HAS A UNIQUE INSTRUCTION MANUAL THAT HAS ALL OF THE INSTRUCTIONS NECESSARY TO DETERMINE THE WAY WE LOOK, THE WAY WE ACT, AND SO MUCH MORE.  

O:  DOUBLE-MAILBAG!

D:  DOUBLE-MAILBAG!

“HELLOOOOOOOOOO, HI JACOB AND OLIVIA.  MY NAME IS BENTLEY.  MY DAD AND I LOVE YOUR PODCAST.  WE LISTEN TO IT EVERY DAY WHEN MY DAD PICKS ME UP AND DROPS ME OFF AT SCHOOL!  WE WANT TO KNOW IF YOU CAN DO A PODCAST ON DNA.

BYE BYE, BENTLEY OF EDMONTON, ALBERTA, CANADA”

“HI, MY NAME IS MILA AND I HAVE A TWIN BROTHER NAMED RICH.  WE LOVE YOUR PODCASTS.  WE LISTEN TO YOUR PODCASTS IN THE CAR AND BEFORE WE GO TO BED.  MY FAVORITE ONE IS THE ONE ABOUT SCORPIONS.  CAN I ASK YOU A QUESTION - HOW DO PEOPLE GET FINGERPRINTS?  AND MY BROTHER’S QUESTION IS HOW DO PEOPLE GET DNA… MUM THINKS A BROADER QUESTION ON GENETICS IS WHAT THEY ARE REALLY CURIOUS ABOUT!  WE CAN’T WAIT TO KEEP LISTENING TO YOUR PODCASTS!

MILA AND RICH OF SYDNEY, AUSTRALIA”

O:  THANKS SO MUCH FOR THOSE GREAT E-MAILS.  WE CAN’T WAIT TO LEARN MORE ABOUT DNA FOR BENTLEY, MILA, AND RICH.  THIS EPISODE IS GOING TO BE D - N - AMAZING!

D:  ALSO, IF YOU WANT TO LEARN MORE ABOUT FINGERPRINTS, WE GOT CURIOUS ABOUT FINGERPRINTS BACK IN EPISODE 164, AND THAT EPISODE WAS AWESOME, SO GIVE IT A LISTEN IF YOU HAVEN’T YET.  

OKAY, SO PREPARE TO HAVE YOUR MIND BLOWN, BECAUSE WE ARE GOING TO LEARN SOME AMAZING FACTS IN THIS EPISODE.  FOR STARTERS, THERE IS A LOT OF DNA IN OUR BODIES.  WE ARE GOING TO LEARN MORE ABOUT WHAT DNA IS AND JUST HOW MUCH IS STUFFED INTO OUR BODIES, BUT CONSIDER THIS.

O:  EVEN THOUGH OUR DNA IS WHAT MAKES EACH OF US UNIQUE, TWO DIFFERENT HUMANS SHARE ABOUT 99.9% OF THEIR DNA.  

D:  THAT MEANS THAT, IF YOU COMPARED YOUR DNA WITH THE DNA OF ANY OF OUR LISTENERS, WHETHER OR NOT THEY ARE RELATED TO US, YOU WOULD SEE THAT 99.9% OF IT IS EXACTLY THE SAME, AND ONLY THE OTHER 0.1% IS RESPONSIBLE FOR THE DIFFERENCES BETWEEN YOU.  

O:  HUMANS AND CHIMPANZEES ALSO SHARE A LOT OF THE SAME DNA, ABOUT 96%.  THAT’S NOT A SURPRISE, BECAUSE CHIMPANZEES ARE NOT MUCH DIFFERENT THAN HUMANS AS FAR AS OTHER ANIMALS GO.

D:  THAT’S TRUE, BUT THIS NEXT ONE MIGHT SURPRISE YOU.  A HUMAN AND A CAT SHARE ABOUT 90% OF THEIR DNA.  

O:  THAT’S CRAZY.  I WOULD NEVER IMAGINE THAT CATS AND HUMANS WOULD HAVE SIMILAR DNA.  CATS ARE NOTHING LIKE US.

D:  WELL, IF YOU WANT TO BE REALLY SURPRISED, SHARE THE QUESTION OF THE WEEK WITH OUR LISTENERS.

O:  THE QUESTION OF THE WEEK IS, HOW MUCH DNA DO HUMANS SHARE WITH BANANAS?  HANG ON A SECOND, MISTER.  THIS CAN’T BE RIGHT.  HUMANS SHARE DNA WITH BANANAS? 

D:  THEY DO, BUT CAN YOU GUESS HOW MUCH?  HANG TIGHT FOR A COUPLE OF MINUTES TO FIND OUT THE ANSWER.  

O:  I THINK WE SHOULD EXPLAIN WHAT DNA IS.  THE LETTERS D-N-A MUST STAND FOR SOMETHING, RIGHT?

D:  THEY SURE DO.  THEY STAND FOR DEOXYRIBONUCLEIC ACID.  GOOD THING WE GET TO SHORTEN THAT TO DNA FOR THE REST OF THE EPISODE.  

O:  THERE IS LOTS OF DNA IN EACH OF OUR BODIES.  I HOPE YOU’RE ALL SITTING DOWN, BECAUSE I’M ABOUT TO HIT YOU WITH SOME SERIOUSLY CRAZY FACTS.  IF YOU STRETCHED OUT THE DNA IN A SINGLE CELL OF OUR BODIES, IT WOULD STRETCH TO ABOUT SIX FEET LONG.  NOT AMAZED YET?  WELL, HUMANS HAVE ABOUT 10 TRILLION CELLS IN THEIR BODIES.  THAT MEANS THAT EACH PERSON HAS ABOUT 60 TRILLION FEET OF DNA SQUISHED INSIDE THEIR BODIES.  THAT’S ABOUT 10 BILLION MILES OF DNA.  THAT MEANS THAT THE DNA IN MY BODY ALONE COULD STRETCH FROM EARTH TO THE SUN AND BACK TO EARTH 61 TIMES.  

D:  NOW THAT WE HAVE AN IDEA OF JUST HOW MUCH DNA EACH OF US HAVE, AND IT’S A WHOLE LOT, LET’S GET A BETTER UNDERSTANDING OF WHAT DNA IS AND HOW IT WORKS TO MAKE US WHO WE ARE.

O:  THE SHAPE OF DNA IS A DOUBLE HELIX.  A DOUBLE HELIX LOOKS LIKE A LADDER THAT IS TWISTED INTO A SPIRAL.  THE SECTIONS OF DNA THAT MAKE US WHO WE ARE ARE CALLED GENES.  

D:  GENES AS IS G-E-N-E-S, NOT J-E-A-N-S LIKE THE JEANS THAT MANY OF US ARE PROBABLY WEARING RIGHT NOW.  THESE GENES ARE TOTALLY DIFFERENT, AND YOU DON’T WEAR THEM.  SO, WE MENTIONED THAT OUR DNA IS SHAPED LIKE A TWISTED LADDER.  EACH ONE OF THE RUNGS OF THAT LADDER HAS A PAIR OF NUCLEOTIDES ON IT.  THERE ARE FOUR NUCLEOTIDE BASES IN TOTAL, AND THEY ARE CALLED ADENINE, THYMINE, CYTOSINE, AND GUANINE.  

O:  THEY ARE OFTEN ABBREVIATED TO THE FIRST LETTERS OF EACH OF THEIR NAMES, WHICH ARE A, T, C, AND G.

D:  THE BASES LOVE PAIRING UP, AND THEY EVEN HAVE PREFERRED FRIENDS TO PAIR UP WITH.  ADENINE, OR A, LOVES TO HANG OUT WITH THYMINE, OR T.  CYTOSINE, OR C, ENJOYS THE COMPANY OF GUANINE, OR G.  

O:  SO, IF YOU CAN PICTURE THE DOUBLE HELIX SHAPE IN YOUR MINDS, ONE RUNG MIGHT BE AN A-T PAIR, AND THE NEXT TWO MIGHT BE C-G PAIRS, THEN YOU MIGHT HAVE ANOTHER A-T PAIR.

WITH JUST FOUR LETTERS IN THE DNA ALPHABET, HOW IS IT POSSIBLE THAT THERE ARE SO MANY DIFFERENT COMBINATIONS OF TRAITS THAT CAN BE MADE FROM A FOUR LETTER ALPHABET?

D:  NOT ONLY IS THE DNA ALPHABET LIMITED TO 4 LETTERS, BUT EACH OF THE WORDS MADE BY THOSE LETTERS IS EXACTLY 3 LETTERS LONG.  BELIEVE IT OR NOT, WITH ONLY 4 LETTERS, THERE ARE 64 DIFFERENT 3 LETTER WORDS THAT CAN BE MADE.  NOW, IF YOU PUT THOSE WORDS INTO A SENTENCE, IMAGINE HOW MANY DIFFERENT COMBINATIONS YOU CAN MAKE. 

O:  HALF OF OUR DNA COMES FROM OUR MOTHERS AND THE OTHER HALF COMES FROM OUR FATHERS.  THAT’S WHY I SHARE SO MANY DIFFERENT TRAITS WITH YOU AND MOMMY.  

D:  THAT’S RIGHT.  AND OUR DNA NOT ONLY DICTATES WHAT WE LOOK LIKE, OR OUR PERSONALITIES, BUT IT ALSO HELPS DETERMINE HOW HEALTHY WE WILL BE.  

O:  DOCTORS ARE EVEN ABLE TO USE GENETIC TESTING TO CHECK FOR POTENTIAL DISEASES BEFORE A BABY IS BORN.  SCIENCE IS AMAZING.

D:  DNA IS FOUND IN OUR BODILY FLUIDS, AND IN OUR HAIR AND SKIN.  CRIME INVESTIGATORS EVEN USE DNA TO GIVE THEM CLUES TO FIND PEOPLE THAT COMMITTED CRIMES.  IF SOMEONE COMMITS A CRIME, SOMETIMES DNA EVIDENCE CAN BE FOUND WHERE THE CRIME TOOK PLACE THAT HELPS TRACK DOWN THE PERSON THAT COMMITTED THE CRIME.  

O:  IT WAS ONLY 35 YEARS AGO IN THE YEAR 1987 THAT DNA WAS USED TO CATCH A CRIMINAL FOR THE FIRST TIME.  

D:  SO MANY ADVANCEMENTS HAVE BEEN MADE WITH DNA IN MY LIFETIME.  PERHAPS THE BIGGEST ONE CAME JUST 21 YEARS AGO, IN 2001.  THAT YEAR, SCIENTISTS WERE ABLE TO MAKE A MAP OF ALL OF THE GENES.  IN OTHER WORDS, THEY DISCOVERED THE ENTIRE DNA sequence, ALSO CALLED THE HUMAN GENOME.  HOW BIG IS THE HUMAN GENOME?  WELL, IT’S ABSOLUTELY MASSIVE.  THE HUMAN GENOME CONTAINS THREE BILLION NUCLEOTIDE BASE PAIRS, LIKE C-G OR A-T.  TO PUT THAT IN PERSPECTIVE, IF YOU SPENT ABOUT EIGHT HOURS A DAY TYPING OUT THE HUMAN GENOME ON A COMPUTER, AND YOU WERE ABLE TO TYPE A WORD EVERY SECOND, IT WOULD TAKE YOU ABOUT 50 YEARS TO TYPE OUT THE ENTIRE HUMAN GENOME.    

O:  SCIENTISTS HAVE EVEN USED DNA TO MAKE CLONES IN A LABORATORY.  A CLONE IS AN EXACT COPY OF LIVING THINGS.  IDENTICAL TWINS ARE CLONES THAT HAPPEN NATURALLY.  IN 1997, SCIENTISTS DID SOMETHING UNBELIEVABLE.  THEY CLONED A SHEEP.  

D:  THIS EPISODE HAD TONS OF SUPER-CRAZY FACTS, AND WE’VE GOT ONE MORE UNBELIEVABLE FACT TO GET TO.  OLIVIA, HOW MUCH DNA DOES A HUMAN SHARE WITH A BANANA?

O:  HUMANS SHARE 41% OF THEIR DNA WITH BANANAS, AND THAT FACT IS JUST BANANAS.  

D:  IF YOU ENJOYED THIS EPISODE, IT PAIRS REALLY WELL WITH EPISODE 65, CURIOUS ABOUT TWINS.  

O:  THE TWO EPISODES MAKE A GREAT PAIR, LIKE A-T AND C-G.  

D:  WELL, THAT’S A WRAP FOR THIS WEEK’S EPISODE.

O:  203 - DNA

D:  GREAT JOB OLIVIA, AND GREAT JOB BENTLEY, MILA, AND RICH, FOR THE BEST TOPIC SUGGESTION ABOUT GENES THAT I’VE EVER SEEN.  WE HAVE SOME SUPER DUPER LISTENERS TO THANK.

O:  THANK YOU TO USERNAME GUMMICANDY FOR THE FIVE STAR REVIEW.  

D:  IT SAYS “I LOVE THIS PODCAST.  MY FAVORITE ONE WAS ABOUT HURRICANES.  I AM 6 AND I LIVE IN NORTH CAROLINA.”

O:  WE ALSO WANT TO THANK OUR NEWEST PATREON SUPPORTERS, OWEN B., LIVVY P., AND CHARLOTTE P.

D: A BIG THANKS TO OWEN, LIVVY, AND CHARLOTTE FOR THE SUPPORT.  JOIN US NEXT WEEK, WHEN WE WILL GET CURIOUS ABOUT PIRATES FOR LISTENERS IN WASHINGTON D.C. AND ARKANSAS.  AS ALWAYS, THANK YOU SO MUCH FOR LISTENING AND GETTING CURIOUS WITH US.