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Abstract: Hereditary spastic paraplegia (HSP) is a neurodegenerative disease characterized by progressive weakness and spasticity of the lower limbs, in complicated forms, with additional neurological signs. To identify the genotype and characterize the phenotype in a Chinese HSP family, ten subjects from the family were examined through detailed clinical evaluations, auxiliary examinations and genetic tests. Using a combined approach of whole-exome sequencing and candidate mutation validation, we identified novel compound heterozygous mutations in the SPG11 gene of the patients as follows: a nonsense mutation c.6856C>T (p.R2286X) in exon 38 and a deletion mutation c.2863delG (p.Glu955Lysfs*8) in exon 16. Both mutations co-segregated with the phenotype in this family and were absent in 100 normal Chinese individuals. Our finding suggests that the novel compound heterozygous mutations in SPG11 are associated with HSP. We were able to assess the future risk of HSP in healthy younger family members using genetic detection, and provide prenatal diagnoses for the family members. Furthermore, to some extent, this new finding enriches the information on SPG11 and may provide a new basis for the genetic diagnosis of HSP. [Copyright &y& Elsevier]

Hereditary nonsyndromic hearing loss is highly heterogeneous and most patients with a presumed genetic etiology lack a specific diagnosis. It has been estimated that several hundred genes may be associated with this sensory deficit in humans. Here, we identified compound heterozygous mutations in the TMC1 gene as the cause of recessively inherited sensorineural hearing loss by using whole-exome sequencing in a family with two deaf siblings. Sanger sequencing confirmed that both siblings inherited a missense mutation, c.589G>A p.G197R (maternal allele), and a nonsense mutation, c.1171C>T p.Q391X (paternal allele), in TMC1. We also used DNA from 50 Chinese familial patients with ARNSHL and 208 ethnicity-matched negative samples to perform extended variants analysis. Both variants co-segregated in family 1953, which had the hearing loss phenotype, but were absent in 50 patients and 208 ethnicity-matched controls. Therefore, we concluded that the hearing loss in this family was caused by novel compound heterozygous mutations in TMC1. [ABSTRACT FROM AUTHOR]