Which of the following characteristics can a lethal gene exhibit?

A gene classified as lethal can exhibit different types of effects depending on its expression and the genetic context in which it operates. Lethal genes can carry recessive lethal effects, where an organism needs to inherit two copies of the lethal allele for it to be lethal, leading to death at an early developmental stage or result in other adverse effects. Alternatively, a dominant lethal effect means that just one copy of the lethal allele will be enough to cause death.

Conditional lethality refers to scenarios where the lethality is dependent on specific environmental conditions or genotypes; for example, an organism may survive under certain conditions but not others due to the effects of the lethal gene. Thus, a lethal gene can demonstrate a range of mechanisms, including recessive, dominant, and conditional lethality, making it capable of exhibiting varied pathways through which it can affect viability. This comprehensive view captures all possible lethal effects that a gene can manifest in different genetic and environmental scenarios.