How can partners with AS genotype make babies that are not SS?
Dad AS, Mum AS. Let’s work it out
A from Dad:
A from Mom AA
S from Mom AS
S from Dad:
A from Mom: AS
S from Dad: SS
That is the beginnings of your answer- you have a 75% chance kid is not SS.
You can stop here if you wish.
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If you want to be scientifically technical, at time of writing, you can go embryo implantation with preimplantation genetic diagnosis (PGD), involves removing a cell from an IVF embryo to test it for a specific genetic condition (cystic fibrosis the most common example) before transferring the embryo to the uterus.