Recently, five cases of osteogenesis imperfecta have been observed at Severance Hospital, Yonsei University. Two newborn females, two female children (one year and eight months, five years and a male child (five years and four months) were typical examples with multiple bone fractures, blue sclerae, and deformity of extremities. The mother of case 3 has also had blue sclera but no history of bone fracture. In case 1, a chromosome study was done because the infant had a short neck, low set ears and a high arched palate besides typical signs of steogenesis imperfecta of which result was found as normal karyotype. In case 3, the patient also presented the rachitic changes of the long bones and ribs and exhibited congenital agenesis of the right kidney. In case 4, the blue sclera was questionable. Three cases on1y have been reported prior to this study in Korea. We are presenting another five cases of osteogenesis imperfecta congenita, its pathology and a brief review of the literature.
Child, Preschool ; Female ; Human ; Infant, Newborn ; Karyotyping ; Male ; Osteogenesis Imperfecta/congenital* ; Osteogenesis Imperfecta/genetics ; Osteogenesis Imperfecta/radiography

OBJECTIVETo study a family affected with osteogenesis imperfecta for potential mutations in COL1A1 gene.

METHODSClinical data of an affected family was collected. Potential mutation of the COL1A1 gene was screened using polymerase chain reaction and direct sequencing. Suspected mutation was detected in 20 unaffected relatives and 200 unrelated healthy controls.

RESULTSAnalysis of RNA splicing has revealed a c.3208G/A mutation, which created a new splice sites and led to a frameshift mutation. The same mutation was not detected in the unaffected relatives or the 200 healthy controls.

CONCLUSIONMutations of the COL1A1 gene are one of the major causes of osteogenesis imperfecta in Chinese population. Our finding has enriched the mutation spectrum of type I collagen genes.

Adult ; Child, Preschool ; Collagen Type I ; genetics ; Female ; Humans ; Male ; Mutation ; Osteogenesis Imperfecta ; genetics ; RNA Splicing

OBJECTIVE: To obtain skin-derived induced pluripotent stem cells (iPSCs) from an Osteogenesis imperfecta (OI) patient carrying WNT1^c.677C>T mutation in order to provide a new cell model for investigating the underlying molecular mechanism and stem cell therapy for OI. METHODS: The pathogenic variant of the patient was identified by Sanger sequencing. With informed consent from the patient, skin tissue was biopsied, and primary skin fibroblasts were cultured. Skin fibroblasts were induced into iPSCs using Sendai virus-mediated non-genomic integration reprogramming method. The iPSC cell lines were characterized for pluripotency, differentiation capacity, and karyotyping assay. RESULTS: The patient was found to carry homozygous missense c.677C>T (p.Ser226Leu) mutation of the WNT1 gene. The established iPSC lines possessed self-renewal and capacity for in vitro differentiation. It also has a diploid karyotype (46,XX). CONCLUSION A patient-specific WNT1 gene mutation (WNT1^c.677C>T) iPSC line was established, which can provide a cell model for the study of OI caused by the mutation.
Humans ; Induced Pluripotent Stem Cells/pathology* ; Osteogenesis Imperfecta/genetics* ; Mutation ; Cell Differentiation/genetics* ; Cell Line

OBJECTIVETo explore genetic mutations and clinical features of osteogenesis imperfecta type V.

METHODSClinical record of five patients (including one familial case) with osteogenesis imperfecta type V were retrospectively analyzed. Peripheral blood samples of the patients, one family member, as well as healthy controls were collected. Mutation of IFITM5 gene was identified by PCR amplification and Sanger sequencing.

RESULTSA heterozygous mutation (c.-14C>T) in the 5-UTR of the IFITM5 gene was identified in all of the patients and one mother. The clinical findings included frequent fractures and spine and/or extremities deformities, absence of dentinogenesis imperfecta, absence of hearing impairment, and blue sclera in 1 case. Radiographic findings revealed calcification of the interosseous membrane between the radius-ulna in all cases. Hyperplastic callus formation was found in 3 cases. Four had radial-head dislocation.

CONCLUSIONA single heterozygous mutation c.-14C>T was found in the 5-UTR of the IFITM5 gene in 5 patients with osteogensis imperfecta type V. The patients showed specific radiological features including calcification of interosseous membrane, hyperplastic callus formation, and radial-head dislocation.

Adolescent ; Adult ; Child ; Child, Preschool ; Female ; Humans ; Male ; Mutation ; Osteogenesis Imperfecta ; diagnostic imaging ; genetics ; Young Adult

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

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

Adult ; Asian Continental Ancestry Group ; genetics ; Collagen Type I ; genetics ; Humans ; Mutation ; Osteogenesis Imperfecta ; genetics ; Pedigree ; Perinatal Death

OBJECTIVE: To explore the genetic basis for a Chinese pedigree with two individuals suffering from congenital blindness. METHODS: Clinical data and peripheral blood samples of the pedigree were collected. Whole exome sequencing was carried out. Suspected variants were verified by Sanger sequencing. Pathogenicity of candidate variants was validated through searching of PubMed and related databases, and analyzed with bioinformatics software. RESULTS: Both patients had congenital blindness and a history of multiple fractures. Other features have included microphthalmia and cornea opacity. One patient had normal intelligence, whilst the other had a language deficit. Both patients were found to harbor compound heterozygous variants of the LRP5 gene, namely c.1007_1015delGTAAGGCAG (p.C336X), c.4400G>A (p.R1467Q) and c.4600C>T (p.R1534X). The first one was derived from their mother, whilst the latter two were derived from their father. None of the three variants was detected in their elder sister. CONCLUSION The compound heterozygous variants of c.1007_1015delGTAAGGCAG (p.C336X) and c.4600C>T (p.R1534X) of the LRP5 gene probably underlay the pathogenesis of the Osteoporosis-pseudoglioma syndrome in this pedigree. The clinical significance of the c.4400G>A (p.R1467Q) variant has remained uncertain. Above finding has enriched the mutational spectrum of Osteoporosis-pseudoglioma syndrome.
Aged ; China ; Humans ; Language ; Low Density Lipoprotein Receptor-Related Protein-5/genetics* ; Mutation ; Osteogenesis Imperfecta/genetics* ; Pedigree

OBJECTIVE: To analyze the clinical phenotype of six pedigrees affected with osteogenesis imperfecta and their genetic basis. METHODS: Peripheral blood or abortic tissues of the six pedigrees were collected for the extraction of genomic DNA. Next generation sequencing (NGS) was carried out to detect pathological variants in the genome. Sanger sequencing was used for validating suspected variant among the six pedigrees and 100 healthy controls. RESULTS: In pedigree 1, the proband and his daughter both carried a heterozygous c.1976G>C variant of COL1A1. The probands in pedigrees 2 to 6 respectively carried heterozygous variants of c.2224G>A of COL1A2, c.2533G>A of COL1A1, c.2845G>A of COL1A2, c.2532_2540del of COL1A1, and c.1847G>A of COL1A2. The same variants were not detected in their parents and the 100 healthy controls. CONCLUSION Variants of COL1A1/2 gene probably underlie the pathogenesis for osteogenesis imperfecta in these pedigrees. Discovery of the nevol variants has enriched the spectrum of COL1A1/2 gene variants and facilitated genetic counseling and prenatal diagnosis for the affected pedigrees.
Collagen Type I ; genetics ; Female ; Genetic Variation ; Genotype ; Humans ; Male ; Mutation ; Osteogenesis Imperfecta ; genetics ; Pedigree ; Phenotype ; Pregnancy

OBJECTIVE: To explore the genetic basis of two fetuses with an osteogenesis imperfecta (OI) phenotype. METHODS: Two fetuses diagnosed at the Affiliated Hospital of Weifang Medical College respectively on June 11, 2021 and October 16, 2021 were selected as the study subjects. Clinical data of the fetuses were collected. Amniotic fluid samples of the fetuses and peripheral blood samples of their pedigree members were collected for the extraction of genomic DNA. Whole exome sequencing (WES) and Sanger sequencing were carried out to identify the candidate variants. Minigene splicing reporter analysis was used to validate the variant which may affect the pre-mRNA splicing. RESULTS: For fetus 1, ultrasonography at 17+6 weeks of gestation had revealed shortening of bilateral humerus and femurs by more than two weeks, in addition with multiple fractures and angular deformities of long bones. WES revealed that fetus 1 had harbored a heterozygous c.3949_3950insGGCATGT (p.N1317Rfs*114) variant in exon 49 of the COL1A1 gene (NM_000088.4). Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), it was classified as a pathogenic variant (PVS1+PS2+PM2_Supporting) for disrupting the downstream open reading frame resulting in premature translational termination, being de novo in origin, and lacking records in the population and disease databases.For fetus 2, ultrasonography at 23 weeks of gestation also revealed shortening of bilateral humerus and femurs by one and four weeks, respectively, in addition with bending of bilateral femurs, tibias and fibulas. Fetus 2 had harbored a heterozygous c.1557+3A>G variant in intron 26 of the COL1A2 gene (NM_000089.4). Minigene experiment showed that it has induced skipping of exon 26 from the COL1A2 mRNA transcript, resulting in an in-frame deletion (c.1504_1557del) of the COL1A2 mRNA transcript. The variant was inherited from its father and had been previously reported in a family with OI type 4. It was therefore classified as a pathogenic variant (PS3+PM1+PM2_Supporting+PP3+PP5). CONCLUSION The c.3949_3950insGGCATGT (p.N1317Rfs*114) variant in the COL1A1 gene and c.1557+3A>G variant in the COL1A2 gene probably underlay the disease in the two fetuses. Above findings not only have enriched the mutational spectrum of OI, but also shed light on the correlation between its genotype and phenotype and provided a basis for genetic counseling and prenatal diagnosis for the affected pedigrees.
Pregnancy ; Female ; Humans ; Osteogenesis Imperfecta/genetics* ; Collagen Type I, alpha 1 Chain ; Collagen Type I/genetics* ; Mutation ; Fetus