Figure 2.

Identification of a Val340Met Gα₁₁ mutation in a family with hypocalcemia and keratoconus. (A) Pedigree of the family, with males and females indicated by squares and circles, respectively. Individuals affected with hypocalcemia, keratoconus, or the combined occurrence of hypocalcemia and keratoconus are indicated by left half‐filled, right half‐filled, or filled symbols, respectively, and unaffected individuals are indicated by open symbols. The proband (individual I.4) is indicated by an arrow, and asterisks indicate those individuals from whom DNA was available for these studies. Plasma calcium (Ca) (mmol/L; normal range = 2.20 to 2.60 mmol/L) and plasma PTH (pg/mL; normal range = 12 to 65 pg/mL) values are shown for individuals I.4, II.3, II.4, and II.5. (B) A heterozygous G>A transition at nucleotide c.1018 within exon 7 of GNA11 (Fig. 1) was identified by WES and confirmed by Sanger DNA sequence analysis. The c.1018G>A GNA11 variant was detected in all four family members with hypocalcemia from whom samples were available. (C) This DNA sequence abnormality was predicted to lead to a missense amino acid substitution of Val to Met at codon 340.