Breeding goats does not produce screaming goat

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I am reopening and confirming this report because the difficulty breeding a screaming goat is distinct from the issue with summoning a screaming goat tracked at MCPE-130746.

Breeding a screaming goat from two non-screaming goats currently has a 1/2500 or 0.04% chance. This is because of how the minecraft:genetics component is set up.

• Goats have 100 possible alleles and 2 of them cause screaming. That gives spawned goats a 2% chance of being screamers.

• Goats also have a 2% chance of mutation when breeding.

• Mutation changes the allele, not the variant.

The result of these rules is that when two normal goats breed, the parent giving the main allele has a 2% chance of giving a random allele, and then the random allele has another 2% chance of being a screamer allele. This gives a 2% * 2% = 0.04% or 1/2500 chance of a normal parent producing a screamer offspring.

If the intended behavior is for breeding normal goats to have a 2% chance of producing a screamer, then one way to achieve this would be to remove the global "mutation_rate": 0.02, parameter from the the minecraft:genetics component and instead to put "mutation_rate": 0.0, under the screamer variant and "mutation_rate": 1.0, under the normal variant. The official genetics documentation says that this should be possible, but in fact doing so gives a content log error saying that the child "mutation_rate" is not valid inside "genetic_variants".

This is what the whole component would look like:

"minecraft:genetics": {
        "genes": [
          {
            "name": "goat_variant",
            "use_simplified_breeding": true,
            "allele_range": {
              "range_min": 1,
              "range_max": 100
            },
            "genetic_variants": [
              {
                "main_allele": {
                  "range_min": 1,
                  "range_max": 2
                },
                "mutation_rate": 0.0,
                "birth_event": {
                  "event": "minecraft:born_screamer",
                  "target": "self"
                }
              },
              {
                "main_allele": {
                  "range_min": 3,
                  "range_max": 100
                },
                "mutation_rate": 1.0,
                "birth_event": {
                  "event": "minecraft:born_default",
                  "target": "self"
                }
              }
            ]
          }
        ]
      },

Any news with this issue? I've been breeding goats for three days and still no sign of a screaming goat, there should have been at least 1 

Screaming goats should still have a 1/50 chance to spawn when in the right biomes, I wouldn’t be surprised if this bug was still occurring. I wasted hours trying to breed goats for a screaming one, found out about the bug and just waited until I got one via natural spawns. I then continued breeding the screaming goats until it was 100% guaranteed a screaming goat.

Yeah a good 6-7 hour a day 3 days straight breeding, I'm thinking it either could still be buggy or I should go and try breed them in their own biome

Yeah definitely just go to the biomes they spawn in and wait around until one naturally generates, killing the goats that aren’t screaming goats will help speed it up

So is this still an issue? 3 Shulker of Wheat in 1.20 - 2 Shulker in 1.21. No screamer. One Shulker approx. 800 goats…