By the year 2010, 17.8 million youths aged 16-19 will work, up from 16 million in 2000, according to government forecasts. Young workers suffer a disproportionate share of injuries and fatalities, especially in the first year on the job. In 2006, 30 youths under 18 died from work-related injuries.
A mutation may or may not affect the amino acid sequence. A mutation may or may not affect the phenotype. Some specific mutations in a gene may have more adverse affects than other mutations in the same gene. A mutation is not necessarily bad. It may even be good. A mutation may enhance or positively change the function of the protein produced by the gene.
Most mutations that damage a DNA strand are harmful. Other mutations occur due to deletion or insertion of DNA base pairs. One such deletion in humans confers HIV resistance or a delayed AIDS onset. Humans who are heterozygous for the mutation, meaning they possess one mutant gene and one normal gene, experience a slower progression of AIDS.