Survivable Birth Defects and the Rise of Mutants

What I want to know is with a 15 fold rise in birth defects and one hospital reporting that 70% of babies born in a month had some kind of deformity, what is the probability of there being some kind of physically beneficial birth defect......

....or at the very least, non-detrimental ones?

Also, is it possible that a particular mutation can be passed into subsequent generations?

More specifically: in a few hundred years, will we have to worry about a hoarde of mutants rising up out of radioactive waste zones to exact revenge against the world?

Does the same reasoning apply to bacteria, which are extremely adaptable to their environments?

Suppose that a culture of E. Coli were exposed to some ionizing radiation that damaged their DNA in such a way as to cause unpredictable mutations. Could some of the mutated E. Coli prove to be better at adapting to a new environment than the original culture?

I'm sure that the answer is, "yes, but it's improbable;" what I'm interested in knowing, though, is if such a thing has ever been observed experimentally, wherein unpredictable mutations (as opposed to deliberate genetic engineering) lead to a more robust species.

The manner in which natural selection can generate novelty in the form of accumulated hereditary information may be illustrated by the following example. Some strains of the colon bacterium, Escherichia coli, in order to be able to reproduce in a culture medium, require that a certain substance, the amino acid histidine, be provided in the medium. When a few such bacteria are added to a cubic centimeter of liquid culture medium, they multiply rapidly and produce between two and three billion bacteria in a few hours. Spontaneous mutations to streptomycin resistance occur in normal (i.e., sensitive) bacteria at rates of the order of one in one hundred million (1 x 10-8) cells. In our bacterial culture we expect between twenty and thirty bacteria to be resistant to streptomycin due to spontaneous mutation. If a proper concentration of the antibiotic is added to the culture, only the resistant cells survive. The twenty or thirty surviving bacteria will start reproducing, however, and allowing a few hours for the necessary number of cell divisions, several billion bacteria are produced, all resistant to streptomycin. Among cells requiring histidine as a growth factor, spontaneous mutants able to reproduce in the absence of histidine arise at rates of about four in one hundred million (4 x 10-8) bacteria. The streptomycin resistant cells may now be transferred to a culture with streptomycin but with no histidine. Most of them will not be able to reproduce, but about a hundred will start reproducing until the available medium is saturated.

Natural selection has produced in two steps bacterial cells resistant to streptomycin and not requiring histidine for growth. The probability of the two mutational events happening in the same bacterium is of about four in ten million billion (1 x 10-8 x 4 x 10-8 = 4 x 10-16) cells. An event of such low probability is unlikely to occur even in a large laboratory culture of bacterial cells. With natural selection, cells having both properties are the common result.

I hope this isn't a half-baked question but it's in regard to recent news stories about massive rises in birth defects in the Iraqi city of Fallujah since the US assault in 2004, for example http://www.guardian.co.uk/world/2009...-birth-defects and the possibility of future birth defects following radiation exposure in Japan. (Hopefully, this thread will not get derailed by boring political discussion)

What I want to know is with a 15 fold rise in birth defects and one hospital reporting that 70% of babies born in a month had some kind of deformity, what is the probability of there being some kind of physically beneficial birth defect or at the very least, non-detrimental ones? Also, is it possible that a particular mutation can be passed into subsequent generations?

More specifically: in a few hundred years, will we have to worry about a hoarde of mutants rising up out of radioactive waste zones to exact revenge against the world?