Syndrome caused by chromosome abnormality. Normally, humans have 23 pairs of chromosomes, including one pair of sex chromosomes. Any variation from this pattern causes abnormalities. A chromosome may be duplicated (trisomy) or absent (monosomy); one or more extra full sets of chromosomes can be present (see ploidy); or part of a chromosome may be missing (deletion) or transferred to another (translocation). Resulting disorders include Down syndrome, intellectual disability, heart malformation, abnormal sexual development, malignancies, and sex-chromosome disorders (e.g., Turner syndrome, Klinefelter syndrome). Chromosomal disorders occur in 0.5percnt of births; many can now be diagnosed before birth by amniocentesis.

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An anomaly is any occurrence or object that is strange, unusual, or unique.

In the following particular contexts it may refer to:

Astronomy

• Eccentric anomaly, intermediate value used to compute the position of a celestial object as a function of time
• Flyby anomaly, unexpected energy increase during Earth flybys of satellites
• Mean anomaly, measure of time in the study of orbital dynamics
• Pioneer anomaly, observed deviation of the trajectories of various unmanned spacecraft
• South Atlantic Anomaly, region where Earth's inner van Allen radiation belt makes its closest approach to the planet's surface
• True anomaly, angle between the direction of periapsis and the current position of an object on its orbit

Geophysics

• Bouguer anomaly, anomaly in gravimetry
• Free-air anomaly, gravity anomaly that has been computed for latitude and corrected for elevation of the station
• Gravity anomaly, difference between the observed gravity and a value predicted from a model
• Iridium anomaly, very rare element in the Earth's crust
• Magnetic anomaly, local variation in the Earth's magnetic field
• Kursk Magnetic Anomaly, territory rich in iron ores located within Kursk Oblast, Belgorod Oblast, and Oryol Oblast
• Temagami Magnetic Anomaly, large buried geologic structure in the Temagami region of Ontario, Canada

Biology

• Congenital vertebral anomaly, any of several malformations of the spine in animals and infants
• Collie eye anomaly, congenital, inherited, bilateral eye disease of dogs involving the retina, choroid, and sclera
• Coronary artery anomaly, congenital abnormality in the coronary anatomy of the heart
• Ebstein's anomaly, congenital heart defect in which the opening of the tricuspid valve is displaced towards the right ventricle of the heart
• Uhl anomaly, very rare congenital heart disease with a partial or total loss of the myocardial muscle in the right ventricle

Quantum physics

• Anomaly (physics), failure of a symmetry of a theory's classical action
• Conformal anomaly, quantum phenomenon that breaks the conformal symmetry of the classical theory
• Chiral anomaly, anomalous nonconservation of a chiral current
• Gauge anomaly, effect of quantum mechanics that invalidates the gauge symmetry of a quantum field theory
• Global anomaly, anomaly in quantum physics
• Gravitational anomaly, effect of quantum mechanics that invalidates the general covariance of a theory of general relativity
• Mixed anomaly, effect of quantum mechanics
• Parity anomaly, anomaly associated with parity

Science fiction

• Fortean anomaly, as in the work of Charles Fort
• Spatial anomaly, broad term in Star Trek and other science fiction for any sort of extraordinary disruption in the space-time continuum
• Anomaly, shortcut to hyperspace travel in Robert Heinlein's 1950s novels, today called a wormhole
• Anomaly (comics), DC Comics villain
• "Anomaly" (Star Trek: Enterprise), an episode of Star Trek: Enterprise
• Anomaly (Primeval), time portal in TV series Primeval
• Anomalies, small areas in the game S.T.A.L.K.E.R.: Shadow of Chernobyl which have various effects on the game environment
• Anomaly, a bridge to another world in the book series His Dark Materials, by Philip Pullman
• Phobos Anomaly, a level in Doom, Episode 1 Level 8
• Deimos Anomaly, a level in Doom, Episode 2 Level 1

Music

• Anomalies (album), 2005 album by Cephalic Carnage
• "Anna Molly" (word play on "anomaly"), song by Incubus from 2006 album Light Grenades
• "Anomaly", song by Delta-S from 2007 album Voyage to Isis

Other

• Ararat anomaly, object on Mount Ararat claimed to be Noah's Ark
• Konishi anomaly, violation of the conservation of the Noether current associated with certain transformations
• Market anomaly, price distortion on a financial market
• Anomaly in software, anything that differs from expectations, whether the expectations resulted from documentation, experiences or otherwise

See also

• Irregular