Genetic screening and IVF in cases of Fragile X syndrome

I was asked a she'elah regarding genetic screening and IVF in cases of Fragile X syndrome (X shavir).
I was able to find an article written by Dr Eisenberg who mentions (in the name of Dr Avraham Steinberg) that Rav Eliashiv is matir genetic screening and IVF in such cases even when the couple could conceive through normal means.
Could you please clarify what's the generally accepted psak halachah in these cases; what's Sha'arei Tzedek and your institute's position regarding the matter; whether Dr Steinberg was given a written or verbal psak; is it possible to get a copy of the psak halachah or to get in touch with Dr Steinberg?
As the couple in question is Israeli, I would be most grateful if you could send me your answer in Hebrew.

Looking forward to hearing from you.
BeBirkat Kol Tuv,
Rav Elimelech Vanzetta
Rav and Dayan of the Jewish Orthodox Community of Chile