Nearly all cases of Pearson syndrome arise from new mutational events. Mitochondria have extremely poor DNA repair mechanisms, and mutations accumulate very rapidly. Most infants with Pearson syndrome die before age 3, often due to infection or liver
Slow spontaneous healing does occur in the body however this often causes scar tissue formation or disorganised matrix made largely of dense collagen fibres, resulting in the repaired area having poorer mechanical properties than healthy and intact tendons. Because of this, repaired tendons are at greater risk of being re-injured at the repair site and so tendon repair is mostly carried out by surgery. Surgical tendon repair is commonly performed using an autograft or allograft to fill the gap between the two ruptured tendon ends. An autograft is when tendon tissue is taken from one part of the patient’s body and transplanted into the repair site. Allografts use tissue from a donor of the same species.
Myelomeningocele is much like Meningocele as there is a sac that protrudes out of the lower back, however with Myelomeningocele, part of the spinal cord comes out as well, making the infant prone to life threatening infections (“Spina Bifida”). There are several factors that can cause spina bifida. The most known cause of Spina Bifida is lack of folic acid during pregnancy (Basile). It can also be triggered by a defect in any of the genes that help control how the
Achondroplasia can be diagnosed by X-ray findings in most affected individuals. Some individuals who are too young to make a diagnosis with certainty or some who don’t have the symptoms of achondroplasia, genetic testing can be used to identify the mutation in the FGFR3 gene. If a child has already been born then the best genetic testing for achondroplasia would be a physical examination and an x-ray to see the skeletal structure of the baby. This genetic testing is done through a blood analysis. Testing parents for achondroplasia is done by an ultrasound.
Rubenstein-Taybi Syndrome Also Known as RTS this disease is caused by a mutation in the CREBBP and EP300. The CREBBP gene is responsible for making a protein that regulates cell growth and division, its needed for normal fetal development. The EP300 gene plays much of the same role as the CREBBP gene, but is not as often the cause of Rubenstein-Taybi Syndrome. The EP300 gene, unlike the CREBBP gene controls protein development before and after birth. In many of the cases of Rubenstein-Tabi Syndrome no mutation is detected in either the CREBBP or the EP300 gene, in these cases the case is unknown but it is suspected that another unknown gene is responsible.
Cri du chat is one of the most common syndromes caused by chromosomal deletion, affecting between one in twenty-thousand and one in fifty-thousand children. Eighty percent of children affected by the syndrome experience chromosome deletion that comes from their father's sperm rather than their mother's egg. When these deletions in the child's chromosomes occur during the formation of sperm or an egg it is caused by an unequal recombination during meiosis. Recombination usually happens between pairs of chromosomes during meiosis while there are lined up at the metaphase plate. If the pairs of chromosomes do not line up as they should or if the
The abnormal B cells may accumulate in the lymph nodes, spleen and lymphatic tissue, causing painless and progressive swelling. Eventually, Hodgkin's lymphoma can spread from the lymph nodes throughout the body. Because the lymphatic system is part of the immune system, when Hodgkin’s Lymphoma begins to progress it compromises the body’s ability to fight infection. Various types of Hodgkin’s Lymphoma exist. The type is based on the types of cells involved in the disease and their behavior.
PKD1 PKD2 PKHD1 How do people inherit polycystic kidney disease? Most cases of polycystic kidney disease have an autosomal dominant pattern of inheritance. People with this condition are born with one mutated copy of the PKD1 or PKD2 gene in each cell. In about 90 percent of these cases, an affected person inherits the mutation from one affected parent. The other 10 percent of cases result from new mutations in one of the genes and occur in people with no history of the disorder in their family.
Like most cancers, mesothelioma involves the abnormal dividing of cells of a particular part of the body -- in this case, the mesothelium. Mesothelioma is so deadly because it remains dormant for many years and then begins to rapidly expand. The cancer then begins to invade and damage nearby tissue, including the vital organs.
This necessitates early detection of the disorder and frequent monitoring of the cardiovascular system. Fig. 1 Overview of the clinical features of Marfan syndrome.3 Genetic abnormalities in FBN-1 gene Marfan syndrome is an autosomal dominant, heritable disorder which does not show predilection for either sex.4 Its incidence is 1 in 5000 individuals.5 It results form a variety of mutations within the FBN1 gene, which maps to 15q21 and codes for glycoprotein fibrillin-1.6 The FBN1 gene spans 253 kb of DNA and contains 65 exons and its corresponding transcript has a length of 10 kb.7 To date, more than 1750 mutations of the FBN1 gene have been identified with 25% of individuals presenting with de novo mutations without previous family history.2, 5 Most of mutations occur within the 47 tandem repeats of epidermal growth factor-like (EGF) domains in exons 14 to 32, disrupting the highly-conserved cysteine residues which are critical for the correct folding of fibrillin-1 protein and for binding of calcium ions, which determines fibrillin’s shape and stability.1, 8, 9