Editing Meat (section)

=== Genetics ===

{|class="wikitable" style="float:left; margin:10px"
|-
! Trait
! Heritability{{sfn|Lawrie|Ledward|2006|pp=17–22}}
|-
|Reproductive efficiency
|2–10%
|-
|Meat quality
|15–30%
|-
|Growth
|20–40%
|-
|Muscle/fat ratio
|40–60%
|}

Some economically important traits in meat animals are heritable to some degree, and can thus be selected for by [[animal breeding]]. In cattle, certain growth features are controlled by [[Dominance (genetics)|recessive genes]] which have not so far been excluded, complicating breeding.{{sfn|Lawrie|Ledward|2006|pp=17–22}} One such trait is [[dwarfism]]; another is the doppelender or "[[Myostatin|double muscling]]" condition, which causes [[muscle hypertrophy]] and thereby increases the animal's commercial value.{{sfn|Lawrie|Ledward|2006|pp=17–22}} [[Genetic analysis]] continues to reveal the mechanisms that control numerous aspects of the [[endocrine system]] and, through it, meat growth and quality.{{sfn|Lawrie|Ledward|2006|pp=17–22}}

[[Genetic engineering]] can shorten breeding programs significantly because they allow for the identification and isolation of [[gene]]s coding for desired traits, and for the reincorporation of these genes into the animal [[genome]].{{sfn|Lawrie|Ledward|2006|pp=17–22}} To enable this, the genomes of many animals [[genome project|are being mapped]].{{sfn|Lawrie|Ledward|2006|pp=17–22}} Some research has already seen commercial application. For instance, a [[Recombinant DNA|recombinant]] [[Bacteria|bacterium]] has been developed which improves the digestion of grass in the [[rumen]] of cattle, and some features of muscle fibers have been genetically altered.{{sfn|Lawrie|Ledward|2006|pp=17–22}} Experimental [[Cloning|reproductive cloning]] of commercially important meat animals such as sheep, pig or cattle has been successful. Asexual reproduction of animals bearing desirable traits is anticipated.{{sfn|Lawrie|Ledward|2006|pp=17–22}}