The severity of the condition may depend on the timing of infection during pregnancy.Microcephaly is a feature common to several different genetic disorders arising from a deficiency in the cellular DNA damage response. Individuals with the following DNA damage response disorders exhibit microcephaly: Nijmegen breakage syndrome, ATR-Seckel syndrome, MCPH1-dependent primary microcephaly disorder, xeroderma pigmentosum complementation group A deficiency, Fanconi anemia, ligase 4 deficiency syndrome and Bloom syndrome. These findings suggest that a normal DNA damage response is critical during brain development, perhaps to protect against induction of apoptosis by DNA damage occurring in neurons. Treatment
There is no known cure for microcephaly. Treatment is symptomatic and supportive. Because some cases of microcephaly and its associated symptoms may be a result of amino acid deficiencies, treatment with amino acids in these cases has been shown to improve symptoms such as seizures and motor function delays. History
People with small heads were displayed as a public spectacle in ancient Rome.People with microcephaly were sometimes sold to freak shows in North America and Europe in the 19th and early 20th centuries, where they were known by the name "pinheads". Many of them were presented as different species (e.g., "monkey man") and described as being the missing link. Famous examples include Zip the Pinhead (although he may not have had microcephaly), Maximo and Bartola, and Schlitzie the Pinhead,. Zip the Pinhead and Schlitzie the Pinhead, also stars of the 1932 film Freaks, were cited as influences on the development of the long-running comic strip character Zippy the Pinhead, created by Bill Griffith.
Moreover, an association has been established between common genetic variants within known microcephaly genes (such as MCPH1 and CDK5RAP2) and normal variation in brain structure as measured with magnetic resonance imaging (MRI)‍—‌i.e., primarily brain cortical surface area and total brain volume.The spread of Aedes mosquito-borne Zika virus has been implicated in increasing levels of congenital microcephaly by the International Society for Infectious Diseases and the US Centers for Disease Control and Prevention. Zika can spread from a pregnant woman to her fetus. This can result in other severe brain malformations and birth defects. A study published in The New England Journal of Medicine has documented a case in which they found evidence of the Zika virus in the brain of a fetus that displayed the morphology of microcephaly. Microlissencephaly
Microlissencephaly is microcephaly combined with lissencephaly (smooth brain surface due to absent sulci and gyri). Most cases of microlissencephaly are described in consanguineous families, suggesting an autosomal recessive inheritance. Historical causes of microcephaly
After the dropping of atomic bombs "Little Boy" on Hiroshima and "Fat Man" on Nagasaki, several women close to ground zero who had been pregnant at the time gave birth to children with microcephaly. Microcephaly was present in 7 children from a group of 11 pregnant women at 11–17 weeks of gestation who survived the blast at less than 1.2 km (0.75 mi) from ground zero.