a reciprocal translocation heterozygote during meiosis the segregation
of a translocated and a normal chromosome together, giving unbalanced
gametes with duplications and deficiencies leading to non-viable zygotes.
Adjacent segregation is of two kinds depending on whether non-homologous
(adjacent-1) or homologous (adjacent-2) centromeres segregate together.
Adjacent-1 segregation is the usual type of adjacent segregation,
adjacent-2 segregation is rare.