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what causes genetic disorders?

title. could it be your parents are cousins (in my case mums dad and dads dad are brothers, making them very close cousins) hence why out of the 5 children I came out with a genetic disorder? and my grandparents are also cousins but I can’t explain the relation. In Islam cousin relationships are allowed. Did something happen during sex which causes these things?

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Most serious genetic disorders are resesive, this means that you need two coppies of the same faulty gene to suffer with it.

Your parents share around 12.5% of their DNA. Also one set of your grandparents also shared 12.5% of their DNA.

This massively increases the likelyhood of their offspring (children) inheriting 2 copies of the same faulty gene- for over 6% of the offsprings genetic code, they will have 2 identical copies of the same gene.

It's not about how they had sex, it's about who they had sex with.
(edited 3 years ago)
Reply 2
Original post by glassalice
Most serious genetic disorders are resesive, this means that you need two coppies of the same faulty gene to suffer with it.

Your parents share around 12.5% of their DNA. Also one set of your grandparents also shared 12.5% of their DNA.

This massively increases the likelyhood of their offspring (children) inheriting 2 copies of the same faulty gene- for over 6% of the offsprings genetic code, they will have 2 identical copies of the same gene.

It's not about how they had sex, it's about who they had sex with.

what about dominant genetic disorders? They only need one copy of the same faulty gene to have the condition.
Very few serious genetic disorders are caused by a dominant gene.

If your siblings where suffering from a genetic disorder caused by a dominant gene, at least on of your parents and one of your grandparents would be symptomatic.
Reply 4
Original post by glassalice
Very few serious genetic disorders are caused by a dominant gene.

If your siblings where suffering from a genetic disorder caused by a dominant gene, at least on of your parents and one of your grandparents would be symptomatic.

i’m the only one in my family that has a genetic condition but I read the condition can be dominant and its rare but can happen to at least 2 people in the family.
They aren't disallowed in other religions or cultures, but they aren't encouraged either, for the very reasons you asked. There have been several TV programmes about multi generational inter-cousin marriage, and the statistics of having children with genetic issues increases as the gene pool gets smaller. The programme I saw was very sad.
(edited 3 years ago)
I hope you don't mind me asking, but do you blame your parents?
Reply 7
Original post by Nautilus
I hope you don't mind me asking, but do you blame your parents?

I believe in God, so I think God gave me this condition because he knows i can handle it, but I also think if theres anyone you can blame in this world its my parents, I screamed at them when I found out the name of the condition at 17, but knew I had 6 problems when I was younger, turns out I have way over 6.
This is so sad. Hopefully the next generation will be better educated.
Reply 9
Original post by Nautilus
I hope you don't mind me asking, but do you blame your parents?

when I screamed at my mum she said loads of people who are cousins get married and have kids, nothing happens to their kids. My eldest sister would say the same thing to me to defend them. Its like I am disabled and living a harder life because of them. I tell my mum and sister “yeah because its so ****ing rare”
In some cases genetic disorders can be caused by spontaneous mutations, given your family history that is unlikely.

If your disease was caused by a dominant gene, one of your parents would also have that disease. Ie. They passed the disease down to you.
If your disease was caused by a recessive gene, both of your parents must be at least carriers. Carriers are non symptomatic.

The ill effects of interbreeding have been observed and recorded throughout history.

Is there someone who you talk about this to?
(edited 3 years ago)
maybe your parents haven't heard of Charles II of Spain who was the product of decades of inbreeding done by the Hapsburg royals in order to prevent their royal blood from being tainted. He was, according to karger.com, physically disabled, disfigured, mentally ******ed, and he proved impotent. He had an inbreeding coefficient of .25, about the same as (or even higher than) that of an offspring from parents who're frickin siblings. They should (no offense) read more articles about the impact of inbreeding, both negative and positive (well, mostly negative), on the offspring.
Original post by glassalice
In some cases genetic disorders can be caused by spontaneous mutations, given your family history that is unlikely.

If your disease was caused by a dominant gene, one of your parents would also have that disease. Ie. They passed the disease down to you.
If your disease was caused by a recessive gene, both of your parents must be at least carriers. Carriers are non symptomatic.

The ill effects of interbreeding have been observed and recorded throughout history.

Is there someone who you talk about this to?

I don’t really speak to anyone about this because if you talk about sex and blame the parents people say you are disgusting. My parents don’t have the disorder so it couldn’t have been dominant, or it could be any of my mums siblings who all died apart from 1 (so 9 others but they weren’t educated so they didn’t know this) and then randomly passed down. The disorder is called by 11p15.5 loss of methylation, meaning a section of chromosome 11 that controls growth doesn’t work which isn’t passed down, or caused by Maternal Uniparental Disomy of Chromosome 7 meaning I have 2 of my mums chromosome 7s and that is passed down. One sibling of my dads died so I don’t know if she had it. Sometimes the genetic cause is negative, but doesn’t rule out a clinical diagnosis, so just with doctors looking at you and telling you you have it. there are other causes but no one knows what they are yet.
I'm sorry that your parents aren't being very nice. I think they are being defensive because they feel guilty. It sounds like they could possibly be carriers of these defective genes. You sound like you have done a lot of reading around the subject. Are you able to talk to the doctor without either of your parents being present?
(edited 3 years ago)
what about things like sickle cell anaemia? a girl died at 17, not sure if she blamed her parents or if they were related or anything, don’t think they were, she was half muslim, half jew, half christian, half african and goes on.
Original post by Nautilus
I'm sorry that your parents aren't being very nice. I think they are being defensive because they feel guilty. It sounds like they could pssibly be carriers of these defective genes. You sound like you have done a lot of reading around the subject. Are you able to talk to the doctor without either of your parents being present?

I can, I am 19 turning 20 in a few days so I can definitely go to the doctors without them, but I am not allowed out on my own and right now during this virus I am worried I may be overheard on the phone.
Like someone else has said, you should speak to a doctor when you have the chance, they will have far more answers for you, than anyone on here.

I wish you look.
I must say though, my disorder is the best disorder that you can have, if you had to pick a genetic condition, this is the best one as it doesn’t kill you and a normal SGA person goes through the same thing as someone with this genetic defect, but obviously we go through a tiny bit more. Its just the average feeding difficulties, failure to meet developmental milestones, pre-natal and postnatal growth failure and recurring episodes of hypoglycaemia. First 7 years was tough for me, followed by 3 that weren’t so bad then medical appointments stopped.
Can you eat normally now?
You write very well, and are articulate. You must have done well at school.
Original post by Nautilus
Can you eat normally now?
You write very well, and are articulate. You must have done well at school.

I can’t eat normally to this day, still eat 1 meal a day, at most 2 meals a day.
Thank you, I did do well but struggled with one of my AS levels.

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