![Picture]( https://cdn.pixabay.com/photo/2014/12/10/20/48/medic-563423_960_720.jpg)

**Read [Part 1]( https://steemit.com/fiction/@suesa/journey-through-space-mars-part-1), [Part 2]( https://steemit.com/fiction/@suesa/the-caves-of-mars-mars-part-2), [Part 3]( https://steemit.com/fiction/@suesa/in-sickness-and-in-health-mars-part-3), [Part 4]( https://steemit.com/fiction/@suesa/insanity-mars-part-3), [Part 5]( https://steemit.com/fiction/@suesa/the-settlers-mars-part-5), [Part 6](https://steemit.com/fiction/@suesa/electromagnetic-mars-part-6)**

The first settler’s home is also located in caves underground. It didn’t really surprise me when we arrived, the idea isn’t that new after all. What did surprise me was the huge difference on the inside. Our home almost looks like a building, with smooth walls and proper lighting. But the caves the first settlers inhabit? They look very rough. Sure, they tried their best to make them look as homely as possible, but there is only so much you can do to naked rock.

At least their “hospital” is better equipped than ours. As soon as we had arrived, they had put me and the other patients in separate beds and given us medication. I had immediately fallen asleep and when I woke up, I felt so much healthier.

Now, I’m just sitting on my bed, waiting for the doctor to discharge me.

It doesn’t take long for the tall, brunette woman to reach me. With experienced movements, she checks my temperature, color of my throat, swelling of my lymph nodes and several other body parts in just a few minutes.

*”You seem to be alright”*, she finally declares. *”I’d like to keep you at our station for a few more days before you return home, just to be sure. But I deem you healthy enough to move freely through our caves. So if you want to become acquainted with the people living here, you’re free to do so.”*

I thank her and enthusiastically leave my bed. It was about time! I am surprised I didn’t bore myself to death. Just think about it, you arrive on a strange planet, there are so many adventures ahead of you. And what happens? You die because you’re so bored. Tragic.

With my eyes wide open and my mind ready to learn as much about this group of humans as possible, I walk through the corridors. Most of the people I encounter try to just ignore me, but I can feel their stares as they turn around after I walked past them. Some don’t wait that long and stare me directly in the face. A significant number of those stares is blatantly hostile. They give me cold shivers and I start walking slower. My shoulders move up slightly as I try to make myself smaller. Stand out less. But it isn’t that easy, obviously. Those people have known each other their whole lives. I stand out a lot.

*”Hey, you’re one of the new settlers, aren’t you?”* I turn around. Behind me stands a young woman, maybe around 20, with blonde hair. She gives me a slightly crooked smile. When I don’t respond, her face shows embarrassment. 

*”I’m sorry, that was a dumb question. Of course, you know that I know that you’re new. I just couldn’t think of anything better to start a conversation.”*

That makes me laugh.

*”It’s alright, starting a conversation with a stranger can be quite challenging.”* I extend my arm to offer her my hand. *”I’m Hannah.”*

*”Andromeda”*, the woman says and grabs my hand. *”Nice to meet you.”*

*”The pleasure is all mine”*, I say in a formal tone and try to keep a straight face. But then I burst out laughing. Andromeda gives me a confused look.

*”I’m sorry, I’m sorry”*, I wheeze. *”The whole situation just feels kind of surreal, you know?”*

*”I’m not sure but I guess that only increases that feeling, doesn’t it?”*

*”A little bit”*, I admit and try to stop my laughter. When it finally dies down, Andromeda smiles again.

*”So”*, she says, *”Is there anything you want to know about how we live here? You must be really bored, you’re basically here alone after all. Or are your friends and family here with you?”*

All laughter and amusement vanish immediately and a heavy clump forms in my stomach.

*”My parents are both dead”*, I whisper. *”My dad years ago, but my mom was killed the day Mike arrived at our station. And my two only friends are still there.”*

Andromeda grabs my hand and squeezes it once.

*”I’m sorry.”* She seems to intensely think about something to take my mind off my sad thoughts. *”You know”*, she finally says, *”when the first settlers arrived here, there were only about 300 people. They were selected to be as genetically diverse as possible to allow a lot of interbreeding, but after two centuries, everyone is somehow related to one another. Do you want to know how we solve that problem?”*

Wiping away some isolated tears that had found their way out of my eyes, I nod. I need to do something, anything, and that’s as good as any other option.

*”Alright then, follow me!”* She’s still holding my hand and thus drags me along with her. I need to walk fast, as she’s making big steps. Soon, we arrive at a room that looks a lot like a laboratory.

*”Welcome to our genetics lab!”* Announces Andromeda. *”Every child that’s born in these caves was first modified in here.”*

*”Modified?”* My eyes widen. *”But genetic modification on humans has been outlawed for …”*
I stop.

*”It hadn’t been outlawed when we left earth. And even if it had been, on Mars there are different laws.”*

*”I guess that’s true”*, I say. *”So, what’s done in here exactly?”*

*”To main procedures. Elimination of genetic diseases in fertilized egg cells and repair of DNA damaged by space radiation.”*

*”That’s possible too?”* I’m surprised. If they can fix the damage, why do they need our technology for the shields?

*”Well, to a certain degree”*, Andromeda explains. *”We can’t really repair the damage itself, we only stimulate and assist the natural DNA healing abilities of our bodies. The radiation causes several kinds of damage. It damages sugars, modifies bases and even breaks strands which can lead to cancer. The low gravity impacts DNA repair negatively, which makes everything even worse. Repairing the damage in the whole organism, like we would in an embryo, isn’t possible. We would need to access every single cell in the body!”*

*”And that’s a bit complicated, I guess.”*

*”Oh yes, very complicated. So we do our best to stimulate the repair mechanisms. But the older someone gets, the more DNA damage occurs even without radiation.”*

*”So that’s why you only send people of a certain age to the surface?”* I remember what Mike said when he had arrived. *”Because people of that age can’t be saved anyway?”*

*”That sounds so brutal when you say it like this, but yes. Young people are protected as long as possible. When we turn 30 we have to go through regular checkups to see how damaged our DNA is. And at one point, we’re allowed to go to the surface. Most people don’t live very long after that.”*

*”But that might change when you can use our technology to shield yourselves. You won’t have to die by radiation poisoning anymore.”*

*”That’d be the ideal result”*, Andromeda agrees.

Together, we leave the laboratory and Andromeda continues showing me around the station.

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##### References:
[Radiation, DNA damage and cancer]( https://www.ncbi.nlm.nih.gov/pubmed/10203748)

[Interplay of space radiation and microgravity in DNA damage and DNA damage response]( https://www.nature.com/articles/s41526-017-0019-7)

[Why is space radiation an important concern for human spaceflight?]( https://srag.jsc.nasa.gov/spaceradiation/why/why.cfm)

[Repair of radiation damage to DNA]( https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2409689/)

[Repair of DNA Damage Produced by Ionizing Radiation](https://www.ncbi.nlm.nih.gov/pubmed/10717187)

[DNA Damage & Repair: Mechanisms for Maintaining DNA Integrity]( https://www.nature.com/scitable/topicpage/dna-damage-repair-mechanisms-for-maintaining-dna-344)

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