Reproductive Medicine Center, Department of Obstetrics and Gynecology, First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China; Anhui Province Key Laboratory of Reproductive Health and Genetics, Biopreservation and Artificial Organs, Hefei, People's Republic of China; Anhui Provincial Engineering Research Center, Anhui Medical University, Hefei, People's Republic of China.
Central Laboratory, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Chaoyang, People's Republic of China.
Fertil Steril. 2019 Sep;112(3):569-576.e2. doi: 10.1016/j.fertnstert.2019.05.005. Epub 2019 Jul 4.
To explore the candidate pathogenic gene in a premature ovarian insufficiency (POI) proband from a consanguineous marriage and detect the potential effects of mutation on cellular energy metabolism.
Genetic and functional studies.
Reproductive medicine center.
PATIENT(S): A patient with POI, from a consanguineous family, and her family members were recruited from the Reproductive Center of the First Affiliated Hospital of Anhui Medical University.
INTERVENTION(S): Whole exome sequencing (WES) was performed for the proband. Variation revealed by WES sequencing was validated by Sanger sequencing in her family. Sequencing data were combined with those of other sporadic cases listed in public databases to identify the causative gene.
MAIN OUTCOME MEASURE(S): Rare homozygous nonsynonymous variants were identified and included in subsequent analysis. Metabolic analyzes were performed using Seahorse XFe96 analyzers to measure oxygen consumption and then obtain further results of ATP production and extracellular acidification rate. The differences in energy metabolism measurements between wild type and mutation were analyzed and compared.
RESULT(S): A novel alanyl-tRNA synthetase 2 (AARS2) homozygous mutation (NM_020745: exon2: c.337G>C: p. G113R) was identified in the aminoacylation region using WES. The mutation was highly conserved among species and predicted to be disease causing. AARS2 encodes mitochondrial alanyl-tRNA synthetase, which attaches alanine onto tRNA-ala. AARS2 mutations were previously reported in female leukodystrophy patients with POI. In mitochondrial stress tests, the ATP productions of the mutation group (3.58 ± 0.46 fmol/min/cell) was significantly lower than that of the wild type group (6.96 ± 1.56 fmol/min/cell).
CONCLUSION(S): This is the first report of a homozygous pathogenic AARS2 mutation in POI. This mutation may lead to incorrect aminoacylation of tRNA, affect mitochondrial translation, and cause oxidative phosphorylation defects, which may be responsible for POI.
探索一位来自近亲婚姻的卵巢早衰（POI）先证者的候选致病基因，并检测突变对细胞能量代谢的潜在影响。
遗传和功能研究。
生殖医学中心。
一位来自近亲家庭的 POI 患者及其家庭成员均来自安徽医科大学第一附属医院生殖中心。
对先证者进行全外显子组测序（WES）。WES 测序揭示的变异通过先证者家系的 Sanger 测序进行验证。将测序数据与公共数据库中列出的其他散发性病例的数据相结合，以确定致病基因。
鉴定出罕见的纯合非同义变异，并将其纳入后续分析。使用 Seahorse XFe96 分析仪进行代谢分析，以测量耗氧量，然后获得进一步的 ATP 产生和细胞外酸化率结果。分析并比较野生型和突变型之间能量代谢测量的差异。
使用 WES 在氨酰化区域鉴定出一种新型丙氨酰-tRNA 合成酶 2（AARS2）纯合突变（NM_020745：exon2：c.337G>C：p. G113R）。该突变在物种间高度保守，预测为致病突变。AARS2 编码线粒体丙氨酰-tRNA 合成酶，该酶将丙氨酸连接到 tRNA-ala 上。AARS2 突变先前在伴有 POI 的女性脑白质营养不良患者中报道过。在线粒体应激试验中，突变组的 ATP 产生（3.58±0.46 fmol/min/cell）明显低于野生型组（6.96±1.56 fmol/min/cell）。
这是 POI 中首次报道 AARS2 纯合致病性突变。该突变可能导致 tRNA 的错误氨酰化，影响线粒体翻译，并导致氧化磷酸化缺陷，这可能是导致 POI 的原因。
