????? ??? ?? ?? ?? ? ?? ??? ?? ???? , ?? ??? ????? ??? ?? ?? ?? ????? ??? ?? ?? ?? ???? ?? ??? ?? ??? ??? ?? ??? ? ??? ??? ?? ????.Trichothiodystrophy, usually termed TTD, is actually a rare inherited issue that affects a lot of parts of your body. The hallmark of the problem is hair that is definitely sparse and easily damaged. [from MedlinePlus G