Some partial deletions and partial duplications produce birth defects. These structural variants include deletions, tandem duplications, inversions, mobile element insertions. Mutations consist of replacements, duplications, deletions or shortenings in the CFTR gene. These mutations include single base pair deletions, insertions, duplications, and amino acid changes. Structural variation, which can include insertions, deletions, duplications, and mutations in DNA. This results in deletions and duplications of dosage sensitive genes. This technique allows abnormalities such as deletions and duplications to be revealed. These genes not only underwent gene duplications within chromosomes but also whole genome duplications. The JGCTs without duplications carried point mutations affecting highly conserved residues. It was initially noted that this yeast genome contained many individual gene duplications. SHFM3 is unique in that it is caused by submicroscopic tandem chromosome duplications of FBXW4/DACTYLIN. Many of these genes have arisen through gene duplications of ancestral members of this family. Ancient genome duplications probably occurred in the evolutionary history of all life. This suggests that they originated from a series of gene duplications on these chromosomes. This indicates a possible linkage between gene duplications and the gigantism.