For other uses, see Transition. Definition of transitions and transversions. In genetics, a transition is a point mutation that changes a purine nucleotide to another purine (A â G) or a pyrimidine nucleotide to another pyrimidine (C â T).Approximately two out of three single nucleotide polymorphisms (SNPs) are transitions.Transitions can be caused by oxidative deamination and tautomerization.or other uses, see Transition. Definition of transitions and transversions. In genetics, a transition is a point mutation that changes a purine nucleotide to another purine (A â G) or a pyrimidine nucleotide to another pyrimidine (C â T).
fringe benefit - an incidental benefit awarded for certain types of employment (especially if it is regarded as a right); a limousine is one of the fringe benefits of the job. perk, perquisite. benefit - financial assistance in time of need.
Bona fide fringe benefits can include the contractors expenditures for medical or hospital care, compensation for occupational injuries or illnesses, life insurance, disability and sickness insurance, pensions, vacation and holiday pay.