Synthetic Lethality and Cancer

Cancer has long been an enemy for humans. In fact too long to be honest.

It's time that cancer gets a dose of its own medicine - time for cancer to get scared and I'll tell you why.

From the Journal of Clinical Oncology:

These refer mainly to ovarian and breast cancers:
In a normal cell there are 2 DNA repair pathways; BRCA1 and BRCA2 are human genes that refer to a class known as tumor supressor genes.
Mutations in these have been linked to breast and ovarian cancer.
The concept of synthetic lethality is linked to the DNA repair pathways.
Loss of functional BRCA1/2 affects the choice of DNA double strand break repair pathway (DSB). In normal cells DNA DSB's are repaired by homologous recombination.
Functional BRCA1/2 are needed for repair by homologous recombination and genomic stability.
In the absence (due to mutations) of these genes an alternative repair pathway is used such as non-homologous end joining (NHEJ) and single strand annealing (SSA) which leads to to:
 - cell death
 - cell survival with genomic instability

The concept of synthetic lethality is that when a mutation occurs in either of the 2 genes has no effect but combining the 2 genes leads to the death of that cell.
In cancer therapy this means inhibiting one of these genes where the other is defective.
BRCA and PARP are involved in DNA repair. In cancer cells without the BRCA gene a PARP inhibitor should be used to cause cell death.
This should be selectively lethal to tumour cells but not to normal cells. 

Research and studies

Looking into all the research that takes place in science.

I was naive before.  (This implies that I hope I am no longer naive)

I used to trust every piece of information and research that was presented in newspapers - especially papers such as the METRO.

Little did I know that there is no hard evidence for believing such claims.
As with many things in life you have to take it with a pinch of salt.

Dr Ben Goldacre's recently exploited many of the scandals of drugs companies who provide misleading data.
They can do so like this (as mentioned by him in the TED talks):
- by cherry picking their volunteers
- by stopping their study half way through when their desired results are produced
- or by compraing their drug to a placebo or one they know does not work very well 

more on this can be found on Goldacre's blog: http://www.badscience.net/2012/10/

So drugs companies are profit hungry, ruthless and provide no benefit to patients. Well or so it seems for some companies - some are now ready to release data so we will have to see about that.

On a more positive  note to a study that I thought was good. 

The recent study with ONE MILLION women - testing the effects of smoking.
Source: http://www.bbc.co.uk/news/health-19946427

I am impressed - they used so many volunteers - this to me shows dedication and effort in a genuine attempt to inform the public.

Although i do wonder why they didn't do the same for men. The costs for funding it? Were men less likely to volunteer for something like this? Would men have to be paid more as volunteers?

Just some thoughts that came into my head.

Abortion: the recent claim

This post is all based on comments by the current Health Secretary, Jeremy Hunt.

To put plainly, he has said the limit for abortion should be limited to 12 weeks - this has sparked outrage within the abortion rights campaigners.

now let's examine the issue - there are reasons why we could believe his opinion:

- medical care is improving so a baby born at 24 weeks (the current limit) can expect to survive
-idea of foetus feeling pain at this point

also important stat to consider which may influence decisions before we discuss the opposing views: 91% of women terminate pregnancy before 13 weeks.

so where does that leave us?

-mothers may make decisions based on the disability of the child etc. and although some testing can be done before 12 weeks others that may confirm it may not be possible until after the 12 weeks.

-sometimes the mother is a vulnerable teenager who hasn't plucked up the courage to tell anybody

-the beginning of life is different to each mother so why should one person have the right to judge?

-because the majority of the mothers do abort before the 12 weeks it seems that it is the most vulnerable who terminate after this date so shouldn't they be given more help.

An even more problematic issue that arises from reducing the abortion limit is that more women would consider the "backstreet" option which is dangerous --> could lead to even more detriment not just to the mother, the economy due to it being illegal it will need police forces to monitor and criminalise -- eventually leading to overall loss.

i'm not sure what to think really just presenting all the reasoning here - i may come with a decision soon.

sources: http://www.bbc.co.uk/news/health-19854465

Epigenetics ...

I was quite amazed when I first discovered the existence of such wonderful science happening in the very cells of my own body.

It is amazing because of what it is. I can't believe that we are not taught this at school.

Epigenetics - could hold the key to many unanswered questions in science, particularly the science of diseases.

So what is it? 

Epigenetics is the mechanism that is beginning to explain we are not just a product of nucleotides sequenced together. Genes can be switched on and off through different environmental factors.

This explains why identical twins - with the exact same DNA - suffer from different diseases and at different points in life.

I am reading Tim Spector's 'Identically Different' for the second time - it's really interesting. I'll come back and discuss some really interesting issues raised in there.  

Keeping up the Olympic Spirit!!!

Okay many of my pedantic friends will tell me that I don't need the 3 exclamation marks for the title. Honestly, I'm just so excited after the Olympics and for sport in general and I can't hide it. Really.

I'm sure there is not a single soul in this country who has not been affected by the Olympics - I mean come on, when are people going to talk about something other than the weather for casual talk?

That's one for a change.
Anyway - yep the positives of the Olympics have been highlighted enough for the media - i don't need to go on about it. however this instance has drawn my attention to gene doping.

I hadn't even heard of the idea before this Olympics. It's shook me to the core. No exaggerations.

Let me give you some background details:
So gene doping is essentially doping by manipulating your genes in particular the genes that are going to enhance your body's performance e.g. the EPO gene that controls red blood cell production. By adding a more enhanced version of the gene, you get more RBC production et voilà more endurance because you can carry more oxygen, hence more aerobic respiration for energy.

This sounds cool.

But, unfortunately this is not allowed. The WADA (world anti-doping agency) are now running genetic tests to see if people are using this. Some people get out of this, I mean how small are genes and how complex are they? So, its not easy to see if you've faltered.

By not using this all that will happen is maybe losing out on a Gold medal (I've heard that losing a gold to a silver is the most disappointing). However, by playing with genes - unmarked territory - you are playing with not only your genes that could potentially develop mutations and then  into cancers - but also if these genes are passed onto future generations we don't know yet what the effects will be.

Should we risk affecting future generations for a gold medal?

Put into perspective that sounds silly doesn't it?

Mitochondria: The Power House!

I had recently read the book 'The Seven Daughter's of Eve' by Bryan Sykes. Brilliantly written book about a fascinating way to trace back to your mitochondrial ancestors.
Put into the book it seems so simple you wonder why nobody thought of it before. To be fair DNA is relatively young and mitochondrial DNA even more so. It makes sense to see why people have been preoccupied with DNA for all this time.

So mitochondria - silent yet ever confident. Our whole lives depend on it.

It took me by surprise when I read a recent article on a genetic disease affecting the mitochondrial DNA. This meaning that it can only be passed on from mother to child and if she has a daughter from her daughter to  her children and so on and so forth.

It's called Leigh's Disease.

It is a disease that affects the brain and the nervous system and leads to death in early childhood.

Now what I'm trying to get at is the ethical issues behind this scenario. If parents affected by this are having to watch their children suffer and die is that fair?
It introduces a new case of 'Three parent IVF' where as well as the sperm and egg from the parents a third donor parent with DNA without the disease alleles can be included.

This seems revolutionary until we start asking questions such as:
Does the third person donating the "right" DNA have any right to the child? Can they claim the fact that they gave the child a disease free life? Could they abuse this?

What if the third party is somebody the parents already know? Would that cause tension between the parents later on in life?
Would the child know that they had their faulty genes corrected by someone else? If so, in what way would the child regard the donor? Would it affect their relationship?

Lets leave the idea of the couple and the child, should scientists even be tampering with something such as genetics when they themselves do not fully understand it?

On the other hand:
These parents just want their child to live. The whole thing with manipulating genes for designer babies- really - it seems quite silly when all you want is to stop them from suffering and to see them growing up.

I found this really interesting, check it out here: http://www.bbc.co.uk/news/magazine-19648992

Does being born from two different races prove to be beneficial?

Sorry I haven't been able to write so often but hey that's the busy life of a science girl...

So I happened to stumble upon this fascinating piece of research by just watching TV. Hmm...
Well, this was a Documentary showing that when  people are mixed race there are advantages in terms of health,   physical prowess, resistance to diseases, and certain talents and skills very out of the ordinary.

This is a topic that many scientists have evaded for many years because of its sensitive nature. However, it is interesting because if people who have very different genes mix - and it is an advantage for the human population shouldn't we be encouraged to mix our genes more?