A parent with 35 repeats would be considered normal and would not exhibit any symptoms of the disease. However, that parents offspring would be at an increased risk of developing Huntingtons compared to the general population, as it would take only the addition of one more CAG codon to cause the production of mHTT (mutant HTT), the protein responsible for disease. Huntingtons very rarely occurs spontaneously; it is almost always the result of inheriting the defective gene from an affected parent. However, sporadic cases of Huntingtons in individuals who have no history of the disease in their families do occur. Among these sporadic cases, there is a higher frequency of individuals with a parent who already has a significant number of CAG repeats in their HTT gene, especially those whose repeats approach the number (36) required for the disease to manifest. Each successive generation in a Huntingtons-affected family may add additional CAG repeats, and the higher the number of repeats, the more severe the disease and the earlier its onset. As a result, families that have had Huntingtons for many generations show an earlier age of disease onset and faster disease progression. Non-trinucleotide expansions
The majority of diseases caused by expansions of simple DNA repeats involve trinucleotide repeats, but tetra-, penta- and dodecanucleotide repeat expansions are also known that cause disease. For any specific hereditary disorder, only one repeat expands in a particular gene. Mechanism
Triplet expansion is caused by slippage during DNA replication or during DNA repair synthesis.
Meatal stenosis, making it more difficult or even impossible to urinate, may also occur.On the non-genital skin, the disease may manifest as porcelain-white spots with small visible plugs inside the orifices of hair follicles or sweat glands on the surface. Thinning of the skin may also occur. Psychological effect
Distress due to the discomfort and pain of lichen sclerosus is normal, as are concerns with self-esteem and sex. Counseling can help.According to the National Vulvodynia Association, which also supports women with lichen sclerosus, vulvo-vaginal conditions can cause feelings of isolation, hopelessness, low self-image, and much more. Some women are unable to continue working or have sexual relations and may be limited in other physical activities. Depression, anxiety, and even anger are all normal responses to the ongoing pain LS patients experience. Pathophysiology
Although it is not clear what causes LS, several theories have been postulated. Lichen sclerosus is not contagious; it cannot be caught from another person.Several risk factors have been proposed, including autoimmune diseases, infections and genetic predisposition. There is evidence that LS can be associated with thyroid disease. Genetic
Lichen sclerosus may have a genetic component. A high correlation of lichen sclerosus has been reported between twins and between family members. Autoimmunity
Autoimmunity is a process in which the body fails to recognize itself and therefore attacks its own cells and tissue. Specific antibodies have been found in LS. Furthermore, there seems to be a higher prevalence of other autoimmune diseases such as diabetes mellitus type 1, vitiligo, alopecia areata, and thyroid disease.