Screening of Graves' disease susceptibility genes by whole exome sequencing in a three-generation family

BACKGROUND: Graves’ disease(GD) has a tendency for familial aggregation, but it is uncommon to occur in more than two generations. However, little is known about susceptibility genes for GD in the three-generation family. METHODS: DNA were extracted from three-generation familial GD patient with a strong genetic background in a Chinese Han population. The Whole Exome Sequencing (WES) was utilized to screen the genome for SNVs associated with GD and the Sanger Sequencing was used to confirm the potential disease-causing genes. RESULTS: In the case study, there were five patients with Graves’ disease(GD) from a three-generation family. The SNVs of MAP7D2(c. 452C > T: p. A151V), SLC1A7(c. 1204C > T: p. R402C), TRAF3IP3(c. 209A > T: p. N70I), PTPRB(c. 3472A > G: p. S1158G), PIK3R3(c. 121C > T: p. P41S), DISC1(c. 1591G > C: p. G531R) were found to be associated with the familial GD and the Sanger sequencing had confirmed these variations. Furthermore, PolyPhen-2 score showed that the variants in TRAF3IP3, PTPRB, PIK3R3 are more likely to change protein functions. CONCLUSION: The MAP7D2, SLC1A7, TRAF3IP3, PTPRB, PIK3R3, DISC1 may be the candidate susceptibility genes for familial GD from a three generations family.