Pericentric

Pericentric is an adjective meaning relating to, or occurring near, a center. In biology and genetics, the most common usage concerns the centromere of a chromosome, while in astronomy it can describe an object’s proximity to the center of mass around which it orbits.

In genetics, the pericentric region refers to the portion of a chromosome that surrounds the centromere itself, often including the centromeric and pericentromeric heterochromatic blocks. A pericentric inversion is a chromosomal rearrangement in which a segment that includes the centromere is reversed end to end. Pericentric regions tend to be rich in repetitive DNA and exhibit reduced recombination; inversions can alter gene order and suppress crossing over in the inverted region, with potential evolutionary and reproductive consequences.

In celestial mechanics, a pericentric distance (or pericenter) is the point in an orbit where the moving body is nearest to the primary mass. It is a key parameter for elliptical or hyperbolic trajectories and contrasts with apocenter, the farthest point. Pericentric distances depend on orbital elements such as semi-major axis and eccentricity, and they influence aspects like gravitational interactions and tidal forces in multi-body systems.

Pericentric usage reflects a general concept of proximity to a center, whether within genomes or gravitating systems, and the term appears across disciplines with domain-specific implications.