Showing posts with label DNA. Show all posts
Showing posts with label DNA. Show all posts

Monday, October 3, 2011

With genetic testing, it is now possible to determine many things about a baby before it born. It is routine to run a genetic test in order to ensure that a baby is healthy and normal. If the baby will not be "normal" the parents are given the choice not to continue the pregnancy (which could also be translated as "have an abortion".) Some people consider it wrong to bring into the world a child who will not be "normal". For many people with inherited disabilities, the idea of testing for disabilities is offensive. To them, it means they are not special human beings like everyone.

In the book and movie My Sister's Keeper, two parents have a "designer baby" genetically created to be a blood/organ donor for her sister with cancer (which could also be translated to "spare parts".) Nowadays, families with genetic diseases can arrange to have such a baby. The DNA of each fertilized egg is examined for the defect that passes on the disease. When one is found without the defect, it is placed in the womb.

However, not every such baby is created because of a genetic defect. Some, like the one in My Sister's Keeper, are designed with a certain blood type. Some are created to have certain characteristics, such as black hair or blue eyes. Perhaps the parents wanted a boy or girl. It is becoming easier and cheaper to have a "designer baby", and it causes young couples to make difficult decisions.

Thursday, September 29, 2011

Seeing Double



In July 1996, it was announced that a sheep had been been born at the Roslin Insitute near Edinburgh, Scotland. What was so amazing about this? Dolly was the first clone. She was very famous. A sweater knitted from her wool was placed in a museum. She had several sheep of her own, none of them clones and all healthy. Everyone talked about how humans would be next. But what is cloning, really?

Cloning comes from the Latin root meaning "to cut from". A clone is an organism grown from a single cell of the parent, genetically identical to the parent. To clone Dolly, they took the nucleus from a sheep egg and replaced it with the nucleus from a sheep cell. A little chemical manipulation and "Hello, Dolly". Cloning creates nothing new, it just makes a copy, like having an identical twin.

What happened to Dolly? At three, she showed signs of premature aging, and she passed away at age six - a young age for a sheep. "Goodbye, Dolly" didn't make the news a lot. But why did she die? Because of the cell that was put into the egg. The DNA was six years old when she was born. The egg that was used to produce her came from a six year old sheep, which made her genes six years old when she was born, meaning she aged faster and died a horrible death. Every cloned animal has died a horrible death.

We did not invent cloning. God did. If you've ever grown strawberries, you'll know that runners come off the plants, new plants for next year. These runners are actually clones of the plant. Some types of female insects produce eggs that, when hatched, produce clones of themselves.

Is cloning immoral? For my part, I have no problem with the idea of cloning plants and animals, if our intentions in doing so are right, such as attempting to cure a disease. We were granted dominion over them, and although we shouldn't abuse it, we can do many positive things through cloning plants and animals. We were not, however, given dominion over other humans. Think about it. God said we must not kill other people, but we were told it is alright to kill and eat animals. And furthermore, humans were meant to have two parents (although this is not always the case), but a cloned human could never. This goes directly against the Bible.

Thursday, September 22, 2011

DNA

DNA is short for deoxyribonucleic acid. DNA is what carries the instructions God put into us for what we look like and how our bodies work. Every species of organism has it, except for bacteria. Birds are born with DNA that makes them able to fly. We humans are all different. Some of us are tall, some of us have brown eyes, some of us have curly hair. But humans are generally not born with feathers.

A chromosome is a long strand of DNA wrapped around proteins. A gene is a length of DNA. Our genes are arranged along the chromosome like beads. Each chromosome has many genes. Within a species, a gene for a certain characteristic, such as black hair or blue eyes, is always on the same place on the same chromosome.

Each cell has two copies of each gene, one from each parent. These two same genes are called alleles. The combination of alleles is what makes each individual unique. The number of possible combinations is practically countless, with the thousands of genes in a chromosome.

A cell duplicates its chromosomes, its DNA, before it divides. A DNA is not a single molecule but is, instead, a double one. This gives it the ability to divide and reproduce. DNA is like a twisted zipper, with the bases the interlocking teeth of the zipper.

When DNA is duplicated, the two strands of DNA separate. The zipper unfastens. Enzymes, special proteins that control the speed of chemical reactions in the cell, bring nucleotides, small subunits on the chains of DNA, to the two DNA strands. The nucleotides link up with exposed bases and join together to form new strands attached to the originals. The result is two double strands.

Tuesday, April 20, 2010

Your DNA

What makes you look different than your brother? DNA. What makes your eyes blue? DNA. What makes your hair so curly it's a waste of time to comb it? DNA. DNA ,makes us different than anyone else. OK, you have about forty secret twins in the world. It's a fact. But still, you are a unique person, created and designed by God. Some people may look like you, but there are probably some differences you don't notice because they're so small. Your DNA is unique to you, though. No one has DNA like yours. Here's an example of how unique you are. If you took one man and one woman (hypothetically speaking) you could have more combinations of genetic information than there are atoms in the universe.

Here is what scientists do to use DNA to solve a crime. They usually don't have too much to work with, DNA being so small, but they probably have something like a piece of hair.
1. Prepare the sample. (That takes a lot of work, but it's too much to go into here.)

2. They divide a special gel into columns, called lanes. They place a DNA sample at the beginning of each lane.

3. An electric current is applied. The DNA fragments move independent of each other. This causes each sample to separate into a series of bands.

4. A match of the DNA is made when the bands in a lane of known and a lane of unknown DNA match. This comparison can be made with a computer or done visually.

As I said earlier, DNA is unique to you. If you ever feel like you look like everyone else, think about that, and remember we're all unique in God's eyes, even if it does feel like we were all made in a photocopy machine.