iq a measure of disposition or genes?

Answer 1

Disposition, as I am familiar with the word is about baseline mood. I am restating your question as if you mean is IQ a measure of phenotypical expression of genes or training; the proverbial "Nature vs. Nurture" question.

In the form it is meant to be, IQ is a measure of raw intelligence which is largely genetic. In practice all tests have some bias that reflects our educational experiences and recent (say the past year or so for an adult) mental exercises. To a lesser extent how much you exercise your brain and in what ways does enable your mind to perform a bit better in random problem solving.

Nature vs. nurture; the answer is both, with a large bias towards nature. I think given a normal environment, genes determine our native intelligence, which is what IQ is supposed to measure (how successfully it does that is a whole field of study itself.) However a lot of how our brains work appears to depend on internal reinforcement of synaptic pathways and culling of unused ones, so if you don't exercise your brain ever, you probably won't be as sharp as you might, and in extreme cases (imagine a person placed into complete sensory deprivation from birth) will be crippled mentally, even assuming reasonable ability to communicate and process information.

BTW, this was better suited for Social Sciences > Psychology

Answer 2

For people living in the prevailing conditions of the developed world, IQ is highly heritable, and by adulthood the influence of family environment on IQ is undetectable. That is, significant variation in IQ between adults can be attributed to genetic variation...

Answer 3

both actually.
one without the other is insufficient.