Facial features of children with<unk>  include a broad and square face, deep-set eyes, large cheeks, and a prominent jaw, as well as a flat nose bridge (in the young child; as the child ages it becomes more ski-jump shaped). Eyes tend to be deep-set, close together and upwards-slanted. Eyebrows are heavy with lateral extension. The mouth is the most noticeable feature; both upper and lower lips are full, and the mouth is wide. The mouth curves downwards and the upper lip curves outwards, due to a fleshy philtrum. These facial features become more noticeable as the individual ages, as Mandible growth outstrips that of the maxilla leading to a clear midface hypoplasia. There is also a mild brachycephaly. Disrupted sleep patterns are characteristic of<unk> , typically beginning early in life. Affected individuals may be very sleepy during the day, but have trouble falling asleep and awaken several times each night, due to an inverted circadian rhythm of melatonin. People with<unk>  have engaging personalities, but all also have a lot of behavioral problems. These behavioral problems include frequent temper tantrums, meltdowns and outbursts, aggression, anger, fidgeting, compulsive behavior, anxiety, impulsiveness, and difficulty paying attention. Self-harm, including biting, hitting, head banging, and skin picking, is very common. Behavioral complications in<unk>  are thought to be worsened by issues with sleeping. Repetitive self-hugging is a behavioral trait that may be unique to<unk> . People with this condition may also compulsively lick their fingers and flip pages of books and magazines (a behavior known as "lick and flip"), as well as possessing an impressive ability to recall a wide range of small details about people or subject-specific trivia. Other symptoms can include short stature, abnormal curvature of the spine (scoliosis), reduced sensitivity to pain and temperature, and a hoarse voice. Some people with this disorder have ear abnormalities that lead to hearing loss. Affected individuals may have eye abnormalities that cause nearsightedness (myopia), strabismus, and other problems with vision. Heart and kidney defects also have been reported in people with<unk> , though they are less common.
Smith–Magenis syndrome
Marshall–Smith syndrome
Wilson–Turner syndrome
Bardet–Biedl syndrome
Beckwith–Wiedemann syndrome
Smith–Lemli–Opitz syndrome
Kapur–Toriello syndrome
Smith Martin Dodd syndrome