According to Simon and Farndon (2008), genetic disorders are abnormalities in an individual 's gene or set of genes which could be due to mutations in the DNA. Also, there are thousands of genetic diseases that can occur as it is estimated that the average rate of genomic mutation is about 2x10-8 per nucleotide per genome (Nachman and Crowell, 2000). Furthermore, they can be grouped into three types named single gene disorders, chromosomal disorders and multifactorial conditions (Milewicz, 2007). Firstly, single gene disorders have mutations that affect specific genes. Moreover, they are classified as either autosomal or sex linked and can be dominant or recessive (ibid). Additionally, sex linked disorders can be X or Y linked depending on
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Furthermore, it entails the delivery of a gene to a predetermined target cell to counter the effect of a defective gene (ibid). Monogenic, Suicide and RNAi therapy are the types of gene therapy that can be used depending on the cause of the disease. Moreover, the delivery of these genes can either be inside the body (in vivo) or outside (ex vivo) and with regards to in vivo deliveries, vectors are required and viruses are the most common types of vectors used (Edelstein, 2004). Some examples of viruses that can be used for delivery include adenoviruses, retroviruses and adeno-associated viruses (ibid). As stated by Gould and Favorov (2003), factors such as titer, tropism, immunogenicity, transgene size and cell state need to be considered when choosing the virus for delivery. Although viruses can be very useful in gene therapy, there are limitations to using this type of method to treat diseases. For instance, adenoviruses could cause high immunogenic responses which may eventually lead to death and retroviruses may cause insertional mutagenesis leading to secondary mutations (Edelstein, …show more content…
However, it should be considered that the loss of liver function may not necessarily be as a result of a mutation of a gene in the liver but instead, a defective gene in other organs that may have altered the production or release of significant proteins required for proper liver functioning (Faibanks and Tavill, 2008). If confirmed that the disease is a result of a defective gene in the liver, then a liver transplant would be recommended rather than gene therapy. This is because gene therapy may not work and also, carrying out a liver transplant may prove to be more cost effective. Furthermore, due to the liver’s great regenerative capabilities, donation of part of the liver can be made by a close family member and once transplantation has been conducted successfully, the segment can regenerate (Fausto, 2004). Despite this, there are still some issues associated with liver transplant such as surgery complications (reaction to anaesthetics) and the increased chance of infections caused by immunosuppressive drugs (Medline plus,
Furthermore, it entails the delivery of a gene to a predetermined target cell to counter the effect of a defective gene (ibid). Monogenic, Suicide and RNAi therapy are the types of gene therapy that can be used depending on the cause of the disease. Moreover, the delivery of these genes can either be inside the body (in vivo) or outside (ex vivo) and with regards to in vivo deliveries, vectors are required and viruses are the most common types of vectors used (Edelstein, 2004). Some examples of viruses that can be used for delivery include adenoviruses, retroviruses and adeno-associated viruses (ibid). As stated by Gould and Favorov (2003), factors such as titer, tropism, immunogenicity, transgene size and cell state need to be considered when choosing the virus for delivery. Although viruses can be very useful in gene therapy, there are limitations to using this type of method to treat diseases. For instance, adenoviruses could cause high immunogenic responses which may eventually lead to death and retroviruses may cause insertional mutagenesis leading to secondary mutations (Edelstein, …show more content…
However, it should be considered that the loss of liver function may not necessarily be as a result of a mutation of a gene in the liver but instead, a defective gene in other organs that may have altered the production or release of significant proteins required for proper liver functioning (Faibanks and Tavill, 2008). If confirmed that the disease is a result of a defective gene in the liver, then a liver transplant would be recommended rather than gene therapy. This is because gene therapy may not work and also, carrying out a liver transplant may prove to be more cost effective. Furthermore, due to the liver’s great regenerative capabilities, donation of part of the liver can be made by a close family member and once transplantation has been conducted successfully, the segment can regenerate (Fausto, 2004). Despite this, there are still some issues associated with liver transplant such as surgery complications (reaction to anaesthetics) and the increased chance of infections caused by immunosuppressive drugs (Medline plus,