Human genes include AFF1, AFF2, AFF3, and AFF4. Fusion genes involving AFF1 can produce a rogue activator leading to leukemia. Mutations in AFF2 are implicated in breast cancer. AFF2/FMR2 are found within the placenta and brains on the X chromosome. A trinucleotide repeat disorder involving AFF2 causes X-linked intellectual disability. This is due to the repetition of over 200 genes in the 5’ region of the untranslated helix. With overextension and methylation on this replicated gene (FRM1) is what leads to FRAXE ID - a rare human disease.  This condition is known as FRAXE ID where the hippocampal region of the brain is affected in long term potentiation and it causes mental retardation. The FMR2 gene has been identified as a part of several pathways within the body (the transforming growth factor-β pathway, the Raf/MEK/MAP kinase pathway, and the P13K/PKB pathway). Studies have been performed on knockout mice to prove the detrimental effect it has on the body such as infliction on organ growth, cell growth, and cytoskeletal structure.
