1.Identification of pathogenic variant and preimplantation genetic testing for a Chinese family affected with osteogenesis imperfecta.
Chuang LI ; Rui HOU ; Caixia LIU ; Huan LI ; Jesse LI-LING ; Yuan LYU
Chinese Journal of Medical Genetics 2022;39(1):21-25
OBJECTIVE:
To identify the pathogenic variant for a husband with osteogenesis imperfecta and provide preimplantation genetic testing (PGT) for the couple.
METHODS:
High-throughput sequencing and Sanger sequencing were carried out to identify the pathologic variant in the husband patients. PGT of embryos was performed through direct detection of the mutation site. Meanwhile, chromosome aneuploidy of the blastocysts was screened. Following transplantation, cytogenetic and genetic testing of fetal amniotic fluid sample was carried out during mid-pregnancy. Chromosome copy number variant (CNV) was detected at multiple sites of the placenta after delivery.
RESULTS:
The husband was found to harbor heterozygous c.544-2A>G variant of the COL1A1 gene. The same variant was not detected in either of his parents. PGT revealed that out of three embryos of the couple, one was wild-type for the c.544-2A site but mosaicism for duplication of 16p13.3.11.2. The other two embryos were both heterozygous for the c.544-2A>G variant. Following adequate genetic counseling, the wild-type embryo was transplanted. Amniotic fluid testing confirmed that the fetus had normal chromosomes and did not carry the c.544-2A>G variant. The copy number of chromosomes at different parts of placenta was normal after birth.
CONCLUSION
For couples affected with monogenic disorders, e.g., osteogenesis imperfecta, direct detection of the mutation site may be used for PGT after identifying the pathogenic variant. After adequate genetic counseling, prenatal diagnosis must be carried out to ensure the result.
Aneuploidy
;
China
;
Female
;
Genetic Testing
;
Humans
;
Osteogenesis Imperfecta/genetics*
;
Pregnancy
;
Preimplantation Diagnosis
2.Preimplantation genetic testing for a couple where the husband is affected by osteogenesis imperfecta combined with balanced translocation using karyomapping technique.
Wenbin NIU ; Mingzhu HUO ; Hao SHI ; Yidong LIU
Chinese Journal of Medical Genetics 2021;38(11):1068-1072
OBJECTIVE:
To carry out preimplantation genetic testing (PGT) for a couple where the husband was affected by osteogenesis imperfecta combined with balanced translocation using the karyomapping technique.
METHODS:
Blastocysts were detected using karyomapping, the carrier status of COL1A1 c.760G>A (p.Gly254Arg) variant and the carrier status of the translocated chromosome were analyzed simultaneously.
RESULTS:
For a total of 10 blastocysts, two euploid blastocysts were found to not carry the COL1A1 c.760G>A (p.Gly254Arg) variant but a balanced translocation. After transplanting one of the blastocysts, clinical pregnancy was achieved. Amniocentesis at 18th gestational week and prenatal genetic testing was in keeping with the result of PGT.A healthy female was born at 40+4 weeks gestation.
CONCLUSION
For patients simultaneously carrying genetic variant and balanced chromosomal translocation, PGT can be performed with efficiency by the use of karyomapping method.
Blastocyst
;
Female
;
Fertilization in Vitro
;
Genetic Testing
;
Humans
;
Osteogenesis Imperfecta/genetics*
;
Pregnancy
;
Preimplantation Diagnosis
;
Spouses
;
Translocation, Genetic
3.Osteogenesis Imperfecta Type VI with Severe Bony Deformities Caused by Novel Compound Heterozygous Mutations in SERPINF1.
Sung Yoon CHO ; Chang Seok KI ; Young Bae SOHN ; Su Jin KIM ; Se Hyun MAENG ; Dong Kyu JIN
Journal of Korean Medical Science 2013;28(7):1107-1110
Osteogenesis imperfecta (OI) comprises a heterogeneous group of disorders characterized by bone fragility, frequent fractures, and low bone mass. Dominantly inherited COL1A1 or COL1A2 mutations appear to be causative in the majority of OI types, but rare recessively inherited genes have also been reported. Recently, SERPINF1 has been reported as another causative gene in OI type VI. To date, only eight SERPINF1 mutations have been reported and all are homozygous. Our patient showed no abnormalities at birth, frequent fractures, osteopenia, and poor response on pamidronate therapy. At the time of her most recent evaluation, she was 8 yr old, and could not walk independently due to frequent lower-extremity fractures, resulting in severe deformity. No clinical signs were seen of hearing impairment, blue sclera, or dentinogenesis imperfecta. In this study, we describe the clinical and radiological findings of one Korean patient with novel compound heterozygous mutations (c.77dupC and c.421dupC) of SERPINF1.
Bone Density/genetics
;
Child
;
Collagen Type I/genetics
;
Eye Proteins/*genetics
;
Female
;
Fractures, Bone/genetics
;
Humans
;
Nerve Growth Factors/*genetics
;
Osteogenesis Imperfecta/diagnosis/*genetics
;
Serpins/*genetics
4.Analysis of a case with gonadal mosaicism for COL1A2 variant.
Haiyan ZHU ; Yuanyuan CHEN ; Lili WANG ; Weizhou WANG ; Sheng HE
Chinese Journal of Medical Genetics 2020;37(5):523-526
OBJECTIVE:
To explore the genetic basis for a couple with normal phenotype but repeated pregnancies with fetuses affected by osteogenesis imperfecta.
METHODS:
Whole exome sequencing (WES) was carried out on fetal specimens and parental DNA to detect potential pathologic variants. Suspected variants were verified by Sanger sequencing. Semen sample of the husband was collected for the extraction of genome DNA, and whole genome amplification (WGA) was performed for single sperms isolated from the sample.
RESULTS:
WES has identified a heterozygous c.1378G>A (p.G460S) variant of the COL1A2 gene in the fetus, which was predicted to be pathogenic but not detected in peripheral blood samples of both husband and wife. The heterozygotic variant was detected in semen DNA from the husband. Among 15 spermatozoa, 4 were found to harbor the variant.
CONCLUSION
The fetus was diagnosed with osteogenesis imperfecta, and the gonadal mosaicism probably accounted for the repeated abnormal pregnancies. Possibility of gonadal mosaicism should be considered when counseling couples with normal phenotype and genotype but recurrent abnormal pregnancies and/or births of children with similar phenotypes and genetic variants.
Adult
;
Child
;
Collagen Type I
;
genetics
;
Female
;
Fetus
;
Gonadal Disorders
;
genetics
;
Humans
;
Male
;
Mosaicism
;
Mutation
;
Osteogenesis Imperfecta
;
diagnosis
;
genetics
;
Pregnancy
;
Prenatal Diagnosis
;
Whole Exome Sequencing
5.Molecular diagnosis of a Chinese pedigree with osteogenesis imperfecta type I.
Long-feng KE ; Lin-wen ZHENG ; Hai-hua XIE ; Ai-zhen YAN ; Zhong-yong ZHU ; Feng-hua LAN
Chinese Journal of Medical Genetics 2009;26(1):50-53
OBJECTIVETo perform molecular diagnosis for a Chinese pedigree with osteogenesis imperfecta type I.
METHODSThirty pairs of primers were designed to amplify all the 52 exons, exon boundaries and promoter region of the COL1A1 gene from genomic DNA of peripheral blood cells of the family members. The PCR products were purified and directly sequenced. To check the mutation in normal controls, the genomic DNA from peripheral blood cells of the index patient, his mother and 60 normal controls were analyzed by amplification refractory mutation system.
RESULTSA missense mutation of GAT>CAT was identified at codon 1441 of the COL1A1 gene from the family, which resulted in the replacement of aspartic acid by histidine (D1441H). This mutation was not found in a group of 60 normal controls.
CONCLUSIONThe method for molecular diagnosis of osteogenesis imperfecta was established and a novel COL1A1 gene mutation, D1441H, was identified in the Chinese pedigree with osteogenesis imperfecta type I.
Adult ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; China ; Collagen Type I ; genetics ; Female ; Humans ; Male ; Mutation ; Osteogenesis Imperfecta ; diagnosis ; genetics ; pathology ; Pedigree ; Sequence Analysis, DNA
6.Mutational analysis and prenatal diagnosis of COL1A1 and COL1A2 genes in four Chinese families affected with osteogenesis imperfecta.
Ying BAI ; Xiangdong KONG ; Ning LIU ; Shumin REN ; Hongxiang GUO ; Kaihui ZHAO
Chinese Journal of Medical Genetics 2017;34(5):705-708
OBJECTIVETo detect potential mutations of COL1A1 and COL1A2 genes in four Chinese pedigrees affected with osteogenesis imperfecta (OI) and provide prenatal diagnosis for a fetus at 18th gestational week.
METHODSAll coding regions and exon/intron boundaries of the COL1A1 and COL1A2 genes were analyzed with targeted next-generation sequencing (NGS). Suspected mutations were confirmed with Sanger sequencing in the probands, unaffected relatives and 200 unrelated healthy individuals. Prenatal diagnosis for a high-risk fetus was carried out through Sanger sequencing.
RESULTSThe probands of families 1 and 2 have respectively carried a c.760G>A (p.Gly254Arg) and a c.608G>T (p.Gly203Val) mutation of the COL1A1 gene. For family 3, the proband and his daughter have carried a novel c.299-1G>C splicing mutation of the COL1A1 gene. The same mutation was not found in the fetus of this family. For family 4, the proband has carried a novel c.1990G>C (p.Gly664Arg) mutation of the COL1A2 gene. The four mutations were not found in the unaffected relatives and 200 unrelated healthy individuals.
CONCLUSIONThe mutations of the COL1A1 and COL1A2 genes probably underlie the disease in the four families. NGS combined with Sanger sequencing can provide an effective and accurate method for their genetic and prenatal diagnosis.
Adult ; Child, Preschool ; Collagen Type I ; genetics ; DNA Mutational Analysis ; Female ; High-Throughput Nucleotide Sequencing ; Humans ; Infant, Newborn ; Male ; Mutation ; Osteogenesis Imperfecta ; genetics ; Prenatal Diagnosis
7.Mutation analysis and prenatal diagnosis of COL1A1 gene in a Chinese family with type I osteogenesis imperfecta.
Hui ZHANG ; Dong WU ; Qiaofang HOU ; Zhiyou LIU ; Litao QIN ; Shixiu LIAO
Chinese Journal of Medical Genetics 2014;31(6):730-732
OBJECTIVETo detect mutation of COL1A1 gene in a Chinese family affected with type I osteogenesis imperfecta (OI) and to provide prenatal diagnosis for a fetus at 17th gestational week.
METHODSPolymerase chain reaction, DNA sequencing and restriction endonuclease analysis were used to verify the detected mutation among other members of the family and 100 healthy controls.
RESULTSNo mutation has been detected in the COL1A2 gene in all of the subjects. A heterozygous mutation c.104-1G>C was identified in the COL1A1 gene among all patients from this family. The same mutation was not found in other members from the family and the 100 healthy controls. The mutation was not found in the fetus, and was verified to be a new mutation according to the type I collagen mutation database.
CONCLUSIONThe c.104-1G>C mutation of the COL1A1 gene probably underlies the type I osteogenesis imperfecta in this family. Under the premise of a clear genetic diagnosis, prenatal diagnosis may be provided to reduce the risk for the disease.
Adult ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; Child, Preschool ; Collagen Type I ; genetics ; DNA Mutational Analysis ; Female ; Fetal Diseases ; diagnosis ; genetics ; Humans ; Infant, Newborn ; Male ; Molecular Sequence Data ; Osteogenesis Imperfecta ; diagnosis ; genetics ; Pedigree ; Point Mutation ; Pregnancy ; Prenatal Diagnosis