[Genotypes and phenotypes of nine Uygur children with osteogenesis imperfecta in Xinjiang].

Objective: To explore the genotypes and phenotypes of osteogenesis imperfecta (OI) in Xinjiang Uygur children. Methods: The history of nine Uygur children with OI who were hospitalized in First Affiliated Hospital of Xinjiang Medical University from January 2013 to December 2017 were retrospectively reviewed. They were classified into 4 types according to the classical Sillence classification. The genes associated with OI were detected, and the pathogenic variation was assessed by InterVar and Alamut software according to the American College of Medical Genetics and Genomics (ACMG) recommendations. The phenotypes of children with different genotypes were further analyzed. Results: Nine cases aged 3 years and 6 monthes to 15 years were all clinically diagnosed as OI, the clinical manifes tations were repeated fractures, skeletal deformities,short stature, blue sclera, abnormol hearing, hypoplasia of dentin, and relaxation of Joint ligaments, among whom 6 was type Ⅲ OI, 3 were type Ⅳ OI. Nine mutations in 3 genes (COL1A1, COL1A2, and SERPINF1) were detected, and 5 of them were first reported and were all pathogenic variations. Conclusions: The cinical phenotypes of osteogenesis imperfecta in Xinjiang Uygur are complex and varied, but all of them have fractures and skeletal deformities. Genotype is different from that reported at China and abroad, and the SERPINF1 gene may have a higher incidence in Uyghur population. The genetic heterogeneity and unique gene variation pedigree of Uyghur osteogenesis imperfecta defects further provide a basis for the correlation between genotype and phenotype of osteogenesis defects.

Novel Compound Heterozygous Variants in the LHCGR Gene in a Genetically Male Patient with Female External Genitalia

The LHCGR gene encodes a G-protein coupled receptor that plays a pivotal role in sexual differentiation in males, ovarian development in females and in fertility via its interaction with luteinizing hormone and chorionic gonadotropin. Inactive variants of the LHCGR gene cause Leydig cell hypoplasia (LCH), which is a rare disease and one of the causes of disorder of sexual differentiation (DSD) in males. The aim of this work was to clarify the clinical and molecular characteristics of a 2.75 year old patient with type 1 LCH. Whole exome sequencing was performed for the patient family and variants in the LHCGR gene were validated by Sanger sequencing. Pathogenicity of the missense variant was evaluated by multiple in silico tools. Our Chinese patient, who exhibited DSD, had female external genitalia (normal labia majora and minora, external opening of urethra under the clitoris and blind-ended vagina) and bilateral testis tissues in the inguinal region. Genetic sequencing revealed compound heterozygous variants in the LHCGR gene in the patient, including a novel missense variant in exon 4 (c.349G>A, p.Gly117Arg) and a novel nonsense variant in exon 10 (c.878C>A, p.Ser293*). The missense variant is in the first leucine-rich repeat domain of the LHCGR protein, which is predicted to affect ligand recognition and binding affinity and thus protein function. The patient is molecularly and clinically diagnosed with type 1 LCH, which is caused by novel, compound heterozygous variants of the LHCGR gene. We believe this report will serve to expand the genotypic spectrum of LHCGR variants.