Weeeell... Most of the stuff I've read about the MMR jab is nonsense
however there does seem to be a disturbing connection to the measels virus itself and the development of the parts of te brain most affected by autism.
MMR won't make your kid autistic but if children are exposed to the measels virus too early it can make the underlying condition worse permanently.
Now I'm not suggesting that your should not vaccinate them against measels and the reason I'm not should be fairly obvious.

The vaccine even though it can cause a perminently damaging effect is in incredibly small doses so that the body can handle it.
Without being exposed to the vaccine first the child is likely to get exposed to a fully devoloped version of the virus that's in circulation
and their body not having evolved strategies to deal with the virus by fighting off a severely weakened version of the virus in the vaccine
that means that when the real stuff hits htem the damage is going to cause far more damage to the child than if they were vaccinated.

Of course trying to explain to parents that you need to cause a small amount of brain damage to your child in order to protect them
is obviously not going to be well received and so i can see why the powers that be are trying to keep this stuff secret.
parents are not going to act rationally to the information and try to find alternative ways of defending against measels
these of course won't work and then the parent will be left with a severely damaged child they can't look after.

Like with most cover-ups that we find out about the reason for the cover-up is normally not because of anything malicious at all.
Now that's not to say that the reason is entirely for the general public's benefit either as is the case with the vaccine.
People with more severe autism are a drain on the state because of the payouts for people on benefis since the parents are the carers and can't work.
It works out mutually beneficially to ensure the children don't become hard to look after for the parents so the lie is a white one if an unintentional bonus.