In gene therapy like for that of SCID where do they change the dna?
103980
In gene therapy, no one actually changes the original DNA of the patient. Typically they simply provide a correct copy of the gene in question in the tissues/organs/cells that need the correct gene for the patient to be healthy again. Therefore it is not very important to have the gene-therapy cells/DNA in every cell of the patient; at least in case of SCID. But in some other cases like muscular dystrophy, the gene therapy would need to be done in literally 70% of the body tissues.. now that's a real challenge still waiting to be solved!
1184816
Are you asking about chromosome transformations such as rearrangements and translocations?
762553
gene is the DNA or RNA in animals cell
1005411
Yes, it will be possible to alter human genes and their expression. Research into gene therapy offers hope to people affected with genetic disorders, e.g. Huntington's Disease and Cystic Fibrosis. WRT preventing death, I think that human life span will be greatly increased, for rich people anyway. This will cause a lot of problems for the rest of the world's population, leading to resource shortages. People can be very selfish and greedy and will justify to themselves their right to an extended life time. Death is part of the natural life cycle. In saying that, I still wish people the chance to a peaceful and happy life and not to die before their time. However,  unless we can sustain ourselves in space and find other planets that support life, we will need to die at 90-100 years, to make room and leave resources for the next generations.
775327
Yes, DNA manipulation in post-natal humans, Has Already Been Done, With Some Success, Consider BMT (Bone Marrow Transplant).
19783
TTACGGTCACCAAGCGTG. A mutation is a chemical or physical change that alters the sequence of bases in DNA molecule.Anything that causesmutation is called a MUTAGEN
289433
Increasing evidence suggests nonrandom localization of DNA sequences in the cell nucleus. Changes in intranuclear gene location as a function of transcriptional activity has been established in several experimental systems
458508
ofcourse, using any other Body cell. every cell has DNA
881107
A point mutation occurs in one nucleotide molecule in its triplet codon of 3 nucletides. One of the base pairs is change. For example adenine could become thymadine. This would result in a change of one codon. which if not corrected would change the paticular amino acid of the codon and could affect the protein that the amino acid is a part of. For example a codon coding for a particular amino acid could chacnge to a stop codon and chop off (truncate), the protein at that point resulting in a shortened useless protein.Such mutations cause certain types of mucular dystrophy etc. Point mutations are a  sources of genetic change. and a minority of those chacnges are positive althogh most are neutral ir deleterious. Cosmic rays can cause point mutations. Also carcinogenic chemicals, old age ionising radiation and certain chemicals. (e.g. 5 fluoro uracil etc.)\nDoc. Dan.
229386
it dates back prehistorically like why dinosaurs are so big? it is through adaptation bcos prokaryotic cells can change their DNA and mutate via the pilli so having a nucleus would mean enveloping the chromosomes so no DNA trasfer can be done or it can be but less efficient.
546065
Not a stupid question at all. Mutation (as mentioned above) does occur, though of course it will only affect individual cells and their descendents, not all cells in the individual. There is also a process that is being increasingly studied called genomic imprinting or epigenetic inheritance. These are not DNA sequence changes, like you asked about, but seem to be related to your question. The wikipedia article is a decent introduction but there are other summaries available.
134505
Something doesn't have to be complex to alter DNA. UV light will do it just fine, as will black pepper or PCBs or many other things.\n\nYou seem to be under the impression that to change DNA you need to somehow intercat with it in a complex way, like a person changing the words in a book. That isn't the case.\n\nChanges in DNA  are produced by events that are more like a shotgun fired into a library. Mostly the changes they cause are catastrophic, but a few pellets will just remove a letter here, or change and 'd' into an 'a' somewhere else. The books they strike ramain readbale, although the meaning changes ever so slightly.\n\nYiu don't need anything complex to do that. Nothing complex about a shotgun pellet.
96827
unlike conventional pharmaceutical treatments... which address the manifestation of disease or illness, i.e., symptoms, gene therapy is a potential permanent therapy or cure. \n\nthink about taking daily doses of insulin to treat diabetes or the drug lipitor to lower cholesterol levels... whether its a natural biological product (insulin) or a chemical compound, a patient needs to intake these drugs because they can not be manufactured in the body.\n\nwhat if instead of taking manufactured insulin, you were able to restore the body's natural ability to produce insulin by transfering the insuling gene with a subset of cells or the appropriate organ... you'd end up with a lifetime therapy... not a short term treatment.\n\nI participated in the first ever human clinical gene therapy trials at the NIH... it was to treat a girl with ADA (adenosine de-aminase) deficiency... essentially an immune suppression that leads to the 'boy in the bubble' syndrome where the person is ultra hypersensitive to external antigens. \n\nsome of the challenges and issues then still remain and some are advanced...  gene identification, gene cassette construction, gene transfer, gene expression, longevity, immune rejection, \n\ngene identification - with the completion of the human genome project, many more genes have been identified and available to be used as a cure... \n\ngene cassettes - the genes need to be engineered to produce the appropriate gene product (protein) within the body...\n\ngene transfer - the gene needs to be transfered from outside the body (ex vivo) to the appropriate organ in the body... engineered (think neutered) viruses serve as vehicles to carry the genes... they are further engineered to target specific organs or cells... e.g., liver, T-cells... pros & cons with different viruses exist, e.g., size, infection rate, immune reactivity, etc...\n\ngene expression - once the gene arrives at the desired location, it has to borrow the cells machinery to produce the proteins... the delivered gene can be express transiently or more permanently... usually when its transient, it requires on-going treatment (... not desirable)... but in order to establish a permanent footprint in the DNA, it must be careful not to cause insertional mutagenesis (get stuck in the middle of an essesntial gene and cause untoward damage)\n\nimmune rejection - colds are caused by viruses... viruses are used as gene transfer vehicles... the body tries to fight off a cold... the body tries to fight off the gene transfer vehicles... a severe inflammatory reaction to a gene transfer event can lead to death...\n\nbesides the technical difficulties, there are ethical, legal, social implications (ELSI) associated with gene therapy... so far gene therapy has been discussed in terms of somatic cell thereapy (adult body cells), not germ line therapy (sperm or egg)... it's one thing to affect a single person, but if you make changes to a sperm or egg, then there is the potential now to pass along the changes to the next generation... \n\ngene therapy, much like other advances in biotech/medicine, was overhyped in its early days... the promise of a cure for intractable diseases raised hopes for patients (and investor)... because the expectations were so high the initial results failed to meet them, but continued progress in this area occurrs each year and soon I believe we will realize the full promise of gene therapy.
439861
A translocation of chromosome basically, means the chromosome  experienced a severe trauma of its structural integrity.  Genes may lose, mutate or turn silent or even turn on without any inhibition and therefore this will cause tremendous change to the organism.  most often, the organism will not survive but if the organism survive, the "change" you mention happended.\n\nIn humans, many syndromes are cause by translocation, even the common Down's syndrome are related to translocation of chromsome.  \n\nthis site can give a good summary:\nhttp://arbl.cvmbs.colostate.edu/hbooks/genetics/medgen/chromo/translocations.html
824039
Not sure if this will help but try the link below\n\nhttp://www.answers.com/topic/gene
512125
in biology, mutations are changes to the genetic material. mutations can be caused by copying errors in the genetic material during cell division and by exposure to radiation, chemicals, or viruses, or can occur deliberately under cellular control during processes such as meiosis or hypermutation. mutations can be classified based on the effect on the structure of the genetic material:\n\n1. small scale mutations affecting one or a few nucleotides\na. point mutation: exchange of a single nucleotide for another through translations or transversions\na)i. silent mutations: code for the same amino acid\na)ii. missense mutations: code for a different amino acid; i.e. sickle cell anemia\na)iii. nonsense mutations: code for a stop codon, which can truncate the protein\nb. insertions: add one or more extra nucleotides causing a shift in the reading frame (or frameshift)\nc. deletions: remove one or more nucleotides thus altering the reading frame (or frameshift)\n\n2. large scale mutations in chromosomal structure\na. amplifications or gene duplications: leading to multiple copies of chromosomal regions\nb. deletions of chromosomal regions: leads to loss of the genes coded; deletions in chromosome 5p causes cri-du-chat syndrome, deletions in chromosome 15q results in prader-willi syndrome\nc. translocations: interchange of genetic parts from non-homologous chromosomes thus bringing together separate genes to form functionally distinct fusion genes; translocations in chromosome 21 causes down syndrome \nd. inversions: reversing the orientation of a chromosomal segment thus bringing together separate genes to form functionally distinct fusion genes\n\nto detect small scale mutations affecting one or more nucleotides, a variety of tests can be done which in principle will test either the dna composition or the presence/absence of the gene products.\n\nlarge scale mutations in the chromosomal structures can be detected using karyotyping because the chromosomes with mutations would differ in sizes and shapes when compared to the standard. in general the chromosomes with deletions would be relatively smaller and chromosomes with additions would be relatively bigger than their counterparts, while chromosomes with either inversions and translocations would exhibit bridges and/or rings.
687471
"Currently, severe thalassemia is treated by blood transfusions, and a minority of patients are cured by bone marrow transplantation. Mouse models are proving to be useful in assessing the potential of gene therapy."\n\nhttp://www.ncbi.nlm.nih.gov/books/bv.fcgi?call=bv.View..ShowSection&rid=gnd.section.250