+ indicates present; −, absent; ↑, increased; ↓, decreased; N/A, not applicable; MS, missense; NS, nonsense; SPL, splicing; DEL, deletion; and NML, normal.

*Essentially all cases of PMPS are sporadic, but rare maternally inherited cases are reported.

†A GLRX5 mutation has been described in only one patient.

‡Nonsense mutations have been described only in females.

§MCV is typically normal or increased in female carriers.