Its value depends on the other genes present and the environment. Organisms contain so many genes and require so many different proteins that it is doubtful that the functions of most genes will be understood for many years. Genes are arranged in long strings, which are folded and bundled up into chromosomes. These chromosomes may be seen in some kinds of cells with the help of a microscope. Most kinds of organisms have chromosomes in pairs, one from each parent.
Most chromosomes have some genes that are potentially harmful or even deadly.
Fortunately however, because chromosomes come in pairs, if the gene on one chromosome cannot produce the protein it should, the gene on the matching chromosome probably can produce it, and the organism is healthy. The population is also healthy if it has a wide diversity of chromosomes and genes. Some of the genes that might seem harmful in some circumstances might be just what the animal needs under other circumstances. But think about what happens when the two chromosomes of a pair contain the same harmful gene. Then the harmful effects of the genes are expressed and the animal may die.