Genetic analysis of a Chinese family affected with α-dystroglycanopathy due to variant of B3GALNT2 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a Chinese pedigree affected with recurrent fetal hydrocephalus.@*METHODS@#A couple who had presented at the Affiliated Hospital of Putian College on March 3, 2021 was selected as the study subject. Following elective abortion, fetal tissue and peripheral blood samples were respectively obtained from the abortus and the couple, and were subjected to whole exome sequencing. Candidate variants were verified by Sanger sequencing.@*RESULTS@#The fetus was found to harbor compound heterozygous variants of the B3GALNT2 gene, namely c.261-2A>G and c.536T>C (p.Leu179Pro), which were inherited from its father and mother, respectively.According to the guidelines of American College of Medical Genetics and Genomics, both variants were classified as pathogenic (PVS1+PM2_Supporting; PM3+PM2_Supporting+PP3+PP4).@*CONCLUSION@#The compound heterozygous variants of the B3GALNT2 gene probably underlay the α-dystroglycanopathy in this fetus. Above results have provided a basis for genetic counseling of this pedigree.

Genetic testing and prenatal diagnosis for a family with 10q22.3q23.2 microdeletion / 中华医学遗传学杂志

OBJECTIVE@#To carry out genetic testing for a pregnant woman with mild mental retardation, facial dysmorphism, and a history of adverse pregnancies and provide prenatal diagnosis for her.@*METHODS@#Routine G-banded karyotyping and single nucleotide polymorphism microarray (SNP-array) analysis were performed on the couple and amniotic fluid sample.@*RESULTS@#No karyotypic abnormality was found with the couple and amniotic fluid sample. SNP-array analysis showed that the woman has carried a 7.801 Mb microdeletion in 10q22.3q23.2, which involved 18 OMIM genes including CDHR1, BMPR1A, NRG3, GRID1 and LDB3, which are associated with facial abnormalities, developmental retardation, mental retardation and autism. The fetus also carried a 7.819 Mb deletion in the same region, while the father showed no abnormality.@*CONCLUSION@#Both the pregnant woman and her fetus have carried a 10q22.3q23.2 microdeletion, which has provided guidance for her subsequent pregnancy.

Spectral domain optical coherence tomography quantifies the macular thickness in patients with type 2 dia betes mellitus without significant diabetic retinopathy / 眼科新进展

Objective To observe the retinal thickness of macular in type 2 diabetic mellitus (T2DM) patients without clinical features of diabetic retinopathy (DR).Methods Totally 40 patients (40 eyes) with T2DM without DR and 70 healthy volunteers (70 eyes) from August 2017 to October 2017 were enrolled in this study.Usage of spectral domain optical coherence tomography (SD-OCT) and the software of automatic segmentation to measure the average thickness of total retinal (R),inner retinal layer (IRL) and outer retinal layer namely photoreceptor layer (PL) in macular.The foveal center was divided according to three concentric circle with the diameter of 1 mm,3 mm and 6 mm (including the partition of R total,R-1,R-3,R-6,IRL-1,IRL-3,IRL-6,PL-1,PL-3 and PL-6),and the average retinal thicknesses of these partitions between these two group were compared and analyzed.Results The thickness of PL-1 and PL-3 in no DR group was significantly thinner than that in the normal control group [(71 ± 4)μm vs.(73 ± 3) μm and (66 ± 2) μm vs.(67 ± 2) μm,respectively] (both P ＜ 0.05).In the normal control group,except the IRL-6 and PL-1,the difference of the thickness was significant in the other macular regions between various genders (all P ＜ 0.05).In the male subjects,the thickness of PL-3 and PL-6 in no DR group was significantly thinner than that in the normal control group [(67 ± 2) μm vs.(68 ± 2) μm and (65 ± 2) μm vs.(66 ± 2) μm,respectively] (both P ＜ 0.05).In the female subjects,the mean thicknesses of PL-3 and PL-6 in no DR group was significant thinner than those in normal control group [(65 ± 2) μm vs.(67 ± 2) μm and (63 ± 2) μm vs.(64 ± 2) μm,respectively] (both P ＜ 0.05).There was no obviously difference in the other parts between these two groups,Conclusion The mean retinal thicknesses of the parafovea and perifovea are significantly thinner in no DR group than that of the normal control group.The measurement of the PL thickness of macular by SD-OCT may promote the study of early stage of DR,and become an important biological marker for early monitoring of DR.