Achondroplasia is a genetic disorder with an autosomal dominant pattern of inheritance whose primary feature is dwarfism. In those with the condition, the arms and legs are short, while the torso is typically of normal length. Those affected have an average adult height of 131 centimetres (4 ft 4 in) for males and 123 centimetres (4 ft) for females. Other features can include an enlarged head and prominent forehead. Complications can include sleep apnea or recurrent ear infections. Achondroplasia includes short-limb skeletal dysplasia with severe combined immunodeficiency. Achondroplasia is caused by a mutation in the fibroblast growth factor receptor 3 (FGFR3) gene that results in its protein being overactive. Achondroplasia results in impaired endochondral bone growth (bone growth within cartilage). The disorder has an autosomal dominant mode of inheritance, meaning only one mutated copy of the gene is required for the condition to occur. About 80% of cases occur in children of parents of average stature and result from a new mutation, which most commonly originates as a spontaneous change during spermatogenesis. The rest are inherited from a parent with the condition. The risk of a new mutation increases with the age of the father. In families with two affected parents, children who inherit both affected genes typically die before birth or in early infancy from breathing difficulties. The condition is generally diagnosed based on the clinical features but may be confirmed by genetic testing.Treatments may include support groups and growth hormone therapy.
Dyssomnias are a broad classification of sleeping disorders involving difficulty getting to sleep, remaining asleep, or of excessive sleepiness. Dyssomnias are primary disorders of initiating or maintaining sleep or of excessive sleepiness and are characterized by a disturbance in the amount, quality, or timing of sleep. Patients may complain of difficulty getting to sleep or staying asleep, intermittent wakefulness during the night, early morning awakening, or combinations of any of these. Transient episodes are usually of little significance. Stress, caffeine, physical discomfort, daytime napping, and early bedtimes are common factors. Types
There are over 31 recognized kinds of dyssomnias. The major three groups, along with the group types, include:: 15 Intrinsic sleep disorders: 15 
idiopathic hypersomnia,
narcolepsy,
periodic limb movement disorder,
restless legs syndrome,
obstructive sleep apnea,
central sleep apnea syndrome,
sleep state misperception,
psychophysiologic insomnia,
recurrent hypersomnia,
post-traumatic hypersomnia,
central alveolar hypoventilation syndrome,
Extrinsic sleep disorders – 13 disorders recognized, including: 16 alcohol-dependent sleep disorder,
food allergy insomnia,
inadequate sleep routine. Circadian rhythm sleep disorders, both intrinsic and extrinsic – 6 disorders recognized, including: 16 advanced sleep phase syndrome,
delayed sleep phase syndrome,
jetlag,
shift work sleep disorder. See also
Parasomnia
Sleep problems in women
Somnolence

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