Lethal Gene Example

Fig 1: Achlorophyllus seedling in BARI Begun-4 comparison with normal green seedlings,

3 Days After Germination

Fig 2: Achlorophyllus seedling in BARI Begun-4 (Solanum melongena),

3 Days After Germination

Lethal genes

Have you ever seen a white plant? Probably not. The white colour in plant is due to the presence of the gene which is also responsible for killing the plant born with that gene. Such genes are termed lethal genes. Some lethal genes kill only in the homozygous condition and are recessive lethals. Dominant lethal cause death even when present in the heterozygous condition. I found a seedling born with the gene in BARI Brinjal-4 after days of sowing. It died after 4 days of germination. In the mean time it took nutrition from seed storage. When the store ended it could not survive due to having no chlorophyll and no photosynthesis.