to a similar degree to children without the syndrome, suggesting separate mechanisms for these biases. cause williams syndrome genes asl baz1b bcl7b cldn3 cldn4 clip2 eif4h eln fzd9 fkbp6 gtf2i gtf2ird1 hip1 kctd7 lat2 limk1 mdh2 ncf1 nsun5 por rfc2 stx1a tbl2 trim50 trim73 trim74 wbscr14 wbscr18 wbscr21 wbscr22 wbscr23 wbscr24 wbscr27 wbscr28 williams syndrome is a microdeletion syndrome caused by the spontaneous deletion of genetic material from the chromosomal region 7q11.23. this is a hemizygous deletion, which results in haploinsufficient expression of the 25–27 genes in this region. clip2, eln, gtf2i, gtf2ird1, and limk1 are among the genes typically deleted. hemizygosity for the eln gene, which codes for the extracellular matrix protein elastin, is associated with connective-tissue abnormalities and cardiovascular disease (specifically supravalvular aortic stenosis and supravalvular pulmonary stenosis). elastin insufficiency may also contribute to distinct facies, harsh or hoarse voice, hernias, and bladder diverticula often found in those with williams syndrome. hemizygosity in limk1, gtf2i, gtf2ird1, and perhaps other genes may help explain the characteristic difficulties with visual–spatial tasks. additionally, some evidence shows that the hemizygosity in several of these genes, including clip2, may contribute to the unique behavioral characteristics, learning disabilities, and other cognitive difficulties seen in ws. diagnosis according to the williams syndrome association, its diagnosis begins with the recognition of physical symptoms and markers, which is followed by a confirmatory genetic test. the physical signs that often indicate a suspected case of ws include puffiness around the eyes, a long philtrum, and a stellate pattern in the iris. physiological symptoms that often contribute to a ws diagnosis are cardiovascular problems, particularly aortic or pulmonary stenosis, and feeding disturbance in infants. developmental delays are often taken as an initial sign of the syndrome, as well. if a physician suspects a case of ws, the diagnosis is confirmed using one of two possible genetic tests: micro-array analysis or the fluorescent in situ hybridization test, which examines chromosome 7 and probes for the existence of two copies of the elastin gene. since 98-99% of individuals with ws lack half of the 7q11.23 region of chromosome 7, where the elastin gene is located, the presence of only one copy of the gene is a strong sign of ws. this confirmatory genetic test has been validated in epidemiological studies and has been demonstrated to be a more effective method of identifying ws than previous methods, which often relied on the presence of cardiovascular problems and facial features (which, while common, are not always present). reliance on facial features to identify ws may cause a misdiagnosis of the condition. among the more reliable features suggestive of ws are congenital heart disease, periorbital fullness ("puffy" eyes), and the presence of a long, smooth philtrum. less reliable signs of the syndrome include anteverted nostrils, a wide mouth, and an elongated neck. even with significant clinical experience, reliably identifying williams syndrome based on facial features alone is difficult. this is particularly the case in individuals of non-white backgrounds, where typical ws facial features (such as full lips) are more prevalent. treatment no cure for williams syndrome has been found. suggested treatments include avoidance of extra calcium and vitamin d, and treating high levels of blood calcium. blood-vessel narrowing can be a significant health problem and is treated on an individual basis. physical therapy is helpful to patients with joint stiffness and low muscle tone. developmental and speech therapy can also help children and increase the success of their social interactions. other treatments are based on a patient's particular symptoms. the american academy of pediatrics recommends annual cardiology evaluations for individuals with ws. other recommended assessments include ophthalmologic evaluations, an examination for inguinal hernia, objective hearing assessment, blood-pressure measurement, developmental and growth evaluation, orthopedic assessments on joints and muscle tone, and ongoing feeding and dietary assessments to manage constipation and urinary problems. behavioral treatments have been shown to be effective. in regards to social skills, it may be effective to channel their nature by teaching basic skills. some of these are the appropriate way to approach someone, how and when to socialize in settings such as school or the workplace, and warning of the signs and dangers of exploitation. for phobias, cognitive-behavioral approaches, such as therapy, are the recommended treatments. one of the things to be careful of with this approach is to make sure that the patients' "charming" nature does not mask any underlying feelings. perhaps the most effective treatment for those with ws is music. those affected have shown relative strength in regards to music, albeit only in pitch and rhythm tasks. not only do they show strength in the field, but also a particular fondness for it. music may help with the internal and external anxiety with which these people are more likely to be afflicted. notably, the typical person processes music in the superior temporal and temporal gyri. those with ws have reduced activation in these areas, but an increase in the right amygdala and cerebellum. people affected by ws are supported by multiple organizations, including the canadian association for williams syndrome and the williams syndrome registry. epidemiology williams syndrome has historically been estimated to occur in roughly one in every 20,000 live births, but more recent epidemiological studies have placed the occurrence rate at closer to one in every 7,500 live births, a significantly larger prevalence. as increasing evidence suggests ws is more common than originally noted (about 6% of all genetic cases of developmental disability), researchers have begun to hypothesize a previous underdiagnosis of the syndrome. one suggested factor in the increase in epidemiological prevalence estimates is that a substantial minority of individuals with the genetic markers of ws lack the characteristic facial features or the diminished intelligence considered to be diagnostic of the syndrome, and often are not immediately recognized as having the syndrome. history williams syndrome was first described by j. c. p. williams and his colleagues, who wrote in 1961 of four patients with supravalvular aortic stenosis, mental disability, and facial features including a broad forehead, large chin, low-set, "drooping" cheeks, widely spaced eyes, and wide-set mouth. a year after this report, german physician a. j. beuren described three new patients with the same presentation. this led to the syndrome's full original name, williams-beuren syndrome, which is still used in some medical publications. from 1964 to 1975, small research reports broadened medical knowledge of this syndrome's cardiovascular problems. then in 1975, k. jones and d. smith produced a large-scale report on numerous patients with ws, ranging in age from infancy to adulthood, and described the behavioral and observable physical symptoms in greater detail than previously recorded. society and culture the adjective "elfin" may have originated to describe the facial features of people with ws; before its scientific cause was understood, people believed that individuals with the syndrome, who have exceptionally charming and kind personalities, had extraordinary, even magical, powers. this has been proposed to be the origin of the folklore of elves, fairies, and other forms of the 'good people' or 'wee folk' present in english folklore. in a review of the symptoms and features of the syndrome, laskari, smith, and graham emphasized that many family members of individuals with ws reject use of terminology such as "elfin", as well as descriptions of social symptoms as "cocktail party syndrome". physicians, family members of individuals with ws syndrome, and ws associations alike have called for the curtailment of such terms. one notable person with the syndrome is gabrielle marion-rivard, a canadian actress and singer who won the canadian screen award for best actress in 2014 for her performance in the film gabrielle. another is jeremy vest, member of the how's your news? team, featured in the tv series and film of the same name.