Diseases that mimic ALS. I am 35 yr Female, since December of 2010 I have had twitching in my legs,arms, feet and hands. Recently I have lost muscle in my hand (pinky joint with mild cramping) and forearm, right buttocks (large indent) and both thighs.
Jump to: navigation, search ... Deletion. Deletion is a type of mutation involving the loss of genetic material. It can be small, involving a single missing DNA base pair, or large, involving a piece of a chromosome.Narration Transcription ... s are the result of a loss of a section of the genetic material (chromosome) of the cell. If the deleted segment is small or it does not contain critical genes, the effect on the cell may be small. ~. (1) A deficiency in a chromosome resulting from the loss of a fragment through breakage.
The smallest single base deletion mutations are believed occur by a single base flipping in the template DNA, followed by template DNA strand slippage, within the DNA polymerase active site. Deletions can be caused by errors in chromosomal crossover during meiosis, which causes several serious genetic diseases. Deletions that do not occur in multiples of three bases can cause a frameshift by changing the 3-nucleotide protein reading frame of the genetic sequence.