What´s a Genomic Conflict?

Genomic conflict takes place when genes affecting the same trait experience different selection pressures because they obey different transmission rules or experience opposing selection at different levels of a nested hierarchy. Therefore genomic conflict can arise in two situations which includes multilevel hierarchical selection which occurs when one selection process is contained inside another selection process such as in meiotic drive and cancer, and another situation, when the transmission is asymmetrical so that the different genetic elements in the system do not follow the same transmission pathways.
The former situation of genomic conflict (asymmetrical transmission) can be explained by taking male sterility in flowering plants such as Plantago coronopis as an example. Plantago coronopis is a rosette plant which is gynodioecious; that is, it has two types of flowers which consist of flowers that have both males and female parts and other flowers that only have the female parts and greatly reduced or absent male sterile parts. Several hermaphroditic plant species contain some individuals that produce no viable pollen. These male-sterile plants are effectively females, in contrast to normal individuals that have flowers which both male and female reproductive structures. Since mitochondria are transmitted only in the female line, mitochondrial mutations that enhance female fitness are favoured by natural selection, irrespective of their impact on male fitness. A mitochondrial mutation that reduces male function and improves female function will therefore be selected. However, nuclear genes are transmitted with equal probability through pollen and ovules, and nuclear genes afffecting reproductive organs are selected for equ...

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...ower level response to escape the fate of the upper level response by moving into another 'replicator'. Since genomic conflict lowers fitness at the higher level, such a gene will become extinct by selection.
However in a sexual lineage, sex is capable of combining gemones from different lineages which results in the formation of genetic variation within the nuclear genome. It is also capable of creating genetic variation in cytoplasmic genomes and it creates opportunities for non-chromosomal genetic elements to change hosts. Therefore when gamete fusion is followed by a meiotic division that produces haploid reproductive cells with genetic recombination and segregation, genetic elements are able to become associated with replicators different from their original hosts. Therefore this shows that sexual organisms are more prone to genomic conflict than asexual ones.