I agree. If you had two parents and knew their exact genetic sequence, you would be able to derive a relatively accurate prediction of each of their children's genotype. But, this prediction would not be precise due to a number of factors including, of course, recombination. Across an entire population it gets quite a bit trickier to predict the many different possibilities based on Mendelian inheritance of chromosomes but also based on which genotypes will be selected for and selected against in a population. Depending on environmental conditions and all the other factors that can serve as agents of selection, genotypes can be favored or removed from a population, for example. Because of all the variables that increase variation across a population it would be impossible to predict the genomic sequence of all the individuals in a large population.

There is some evidence that suggests that there is a certain component of intelligence, measured by "IQ" scores, that is genetic. Depending on what you read, the results might seem confusing. But, many reports suggest that there is at least some genetic component to IQ but the heritability of this trait is not as clear as for some other polygenic traits, like height. Most of the studies examining the genetic vs. environmental component of cognition are done by comparing the IQs of monozygotic (identical) twins raised together (considered same environment) or raised apart and dizygotic (fraternal) twins raised together or apart. One complication of some of this data is the fact that much of it comes from scientists comparing many DISTINCT studies in a single comparison. This means that while a scientist reports looking at hundreds of twin comparisons, these may come from multiple different published reports. While there are statistical methods that enable scientists to perform this type of analysis, there are always problems in comparing different studies performed by different investigators under different conditions. It seems clear from all these studies that IQ is incredibly complex. It is a continuous trait, like height, where there are MANY different normal phenotypes. You wouldn't expect everyone to have the same height, right? Remember also that IQ is just one measure of intelligence. Nevertheless, it is still a widely accepted measure. We still do not have techniques that allow us to both identify the many genes that contribute to polygenic, continuous traits and how those genes/alleles interact with the environment. Recent studies have even examined the potential contribution of "maternal effect" on IQ, that is the environment of the womb during gestation. This study (see link below) suggests that the maternal affect may indeed play a very significant role in determination of IQ. It is easy to imagine that if a trait as "simple" as human height (which does clearly exhibit high heritability) is estimated to be controlled by dozen(s) of genes, that something as complex as human intelligence might be controlled by even more. This could then be complicated by maternal environment, age, nutrition, home environment, etc. and it becomes an immense problem to tease out the individual components. As genome-wide association studies become more powerful and more rigorous, digging into complex traits will likely become a more tractable issue. Two articles might help provide some perspective on your question: http://www.nature.com/scitable/content/The-heritability-of-IQ-26372 http://www.nature.com/scitable/topicpage/Heritability-of-Human-Intelligence-IQ-and-Eugenics-796 For a good review on heritability of height, see Weedon and Frayling, 2008 (Trends in Genetics Volume 24, Issue 12, December 2008, Pages 595-603 )

Without taking into consideration the specific types of genes, there have been multiple different methods published that allow for the simultaneous co-expression of multiple genes off of the same expression vector. 1) Utilization of multiple promoters in the same vector with each promoter controlling the expression of a different gene. Often the concern with this is the fact that the 3' promoters are attenuated, resulting in decreased expression from these promoters. 2) Chimeric gene expression. It is also possible for multiple genes to be fused together, put together in tandem in a vector driven off the same promoter. This results in a fusion protein. Unfortunately, not all proteins retain their function. 3) Utilization of a primary promoter and downstream IRES. When downstream genes are separated from upstream genes using an internal ribosomal entry site (IRES) can result in relatively efficient expression of the downstream gene(s). My question for you would be whether you think it matters about the types of genes (antiviral, antifungal... etc) that you would try to co-express? Would the types of genes you include in the vector influence your success? If so, how?

In general the tests themselves are safe, requesting you to take a simple buccal swab (from your mouth) to collect the cells for DNA. But after that, there's a lot open for question. While the test itself is safe, it remains to be seen whether there is a potential danger to individuals psychologically and emotionally when certain results are received at home. These "direct-to-consumer" tests can be misunderstood and individuals mislead if they are not properly informed. Most traits are complex- they are the result of genes and environment working together. Therefore, very little about you can be understood just from knowing your DNA sequence alone. This information together with your family history, your diet, your physical activity and other information should be taken together as part of your medical history. Testing yourself or your children for their ability to excel at marathons is up to you (a recent testing company will test children and tell you the sports they are likely to excel at) but know that while they are using genetics to give you the answer, it is hardly an exact science. For some more information on Direct-to-Consumer tests and the limitations of genetic testing in general, I recommend these links: http://www.nature.com/scitable/topicpage/DTC-Genetic-Testing-for-Diabetes-Breast-Cancer-698 http://www.nature.com/scitable/topicpage/DTC-Genetic-Testing-23andme-DNA-Direct-and-674 http://www.nature.com/scitable/content/Do-it-yourself-diagnosis-11801