a transcript of the official policy for reference
EAZA Position on Intentional Breeding
for the Expression of Rare Recessive Alleles
26 April 2013
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EAZA Position
Breeding practices that increase the phenotypic expression of single rare alleles through intentional inbreeding cause clearly abnormal or aberrant external and internal conditions and characteristics. The predictability of such outcomes from intentional inbreeding to produce phenotypic anomalies indicates that these practices are not in adherence with EAZA codes and practices including the EAZA Constitution (2006), EAZA Code of Practise (2004) and EAZA Code of Ethics (2009).
Thus, EAZA institutions should not engage in such intentional breeding practices for the Expression of Rare Recessive Alleles from the perspectives of welfare, education, population management, and conservation.
In addition, inappropriate breeding practices by others may result in animals expressing rare recessive alleles, which at times are in need of rescue. Therefore, providing holding and care for such animals and responding to rescue requests from local, state, or federal agencies are appropriate activities for EAZA institutions, provided that the delivery of thoughtful educational messages about the unfortunate results of inbreeding are part of any public display.
i believe this was intended to cover white lions, white tigers , golden tigers and king cheetah.