OBJECTIVE This study aimed at identifying inner ear malformation underlying molecular determinant(s) using a large five-generation Chinese family with multiple familial cases. METHODS Model-based genetic linkage analyses were performed with the use of microsatellite polymorphisms to determine the disease locus. Mutation screening was performed with the family and unrelated population-based controls to establish molecular evidence that caused the specific X-linked inheritance pattern in the family. RESULTS Clinical investigations of the pedigree demonstrated the extremely high penetrance in the male members, but no penetrance in the female members. Linkage analyses mapped the disease to the chromosomal region Xq13.1-Xq23 (maximum X-linkage LOD score = 3.27). Mutation screening of the candidate genes in the linkage region by direct sequencing revealed a de novo missense substitution (925T→C) in the well-known deaf gene POU3F4. Direct sequencing on 110 unrelated controls did not detect any mutation. CONCLUSION a novel mutation of POU3F4 gene was identified to be the causative reason for the hearing loss in family with inner ear malformation.

OBJECTIVE To investigate the contribution of the GJB6 gene [encoding connexin 30 (C?30)] mutations in Chinese population with sporadic non-syndromic hearing impairment. METHODS PCR reactions were performed with two pair of primers for the coding sequence of GJB6 gene and for the deletion of GJB6. PCR products bidirectional sequencing was subsequently applied in 214 patients with hearing loss and 86 normal controls. RESULTS A novel heterozygous mutation-233(C→A) was found, which results in amino acid change, A78D. This mutation wasn't detected in the control subjects. The altered valine residue lies within the second conserved transmembrane domain. The large deletion△(GJB6/ D13S1830)] of GJB6 was not found in this group. CONCLUSION The large deletion of GJB6 was not found in the Chinese deafness population. A novel heterozygous mutation of GJB6 was found. These results indicated GJB6 mutations are not a major cause of hearing loss in the Chinese population.

BACKGROUND: Antiphospholipid syndrome (APS) is an autoimmune prothrombotic condition with significant morbidity. The objective of this study was to identify additional clinical and epidemiological risks of arterial thrombosis, venous thrombosis, and pregnancy morbidities in a large cohort of persistent antiphospholipid antibodies (aPLs)-positive carriers. METHODS: This was a cross-sectional cohort study of 453 consecutive patients with a documented positive aPL who attended Peking University People's Hospital. Among 453 patients screened, 297 patients had persistent positive aPL. We compared asymptomatic aPL carriers with thrombotic and obstetric APS patients. And the univariate analysis and multivariable logistic regression were used to evaluate the association between different risk factors and APS clinical manifestations. The levels of circulating markers of neutrophil extracellular traps (NETs) (cell-free DNA and citrullinated histone H3 [Cit-H3]) were assessed and compared among aPL-positive carriers with or without autoimmune disease and APS patients. RESULTS: Additional risk factors associated with arterial thrombosis among aPL-positive carriers included: smoking (odds ratio [OR] = 6.137, 95% confidence interval [CI] = 2.408-15.637, P  = 0.0001), hypertension (OR = 2.368, 95% CI = 1.249-4.491, P  = 0.008), and the presence of underlying autoimmune disease (OR = 4.401, 95% CI = 2.387-8.113, P < 0.001). Additional risks associated with venous thrombosis among aPL carriers included: smoking (OR = 4.594, 95% CI = 1.681-12.553, P  = 0.029) and the presence of underlying autoimmune disease (OR = 6.330, 95% CI = 3.355-11.940, P < 0.001). The presence of underlying autoimmune disease (OR = 3.301, 95% CI = 1.407-7.744, P  = 0.006) is the additional risk, which demonstrated a significant association with APS pregnancy morbidity. Higher circulating levels of cell-free DNA and Cit-H3 were observed among APS patients and aPL patients with autoimmune diseases compared with those aPL carriers without underlying autoimmune diseases. Furthermore, control neutrophils that are conditioned with APS patients'sera have more pronounced NET release compared with those treated with aPL carriers'sera without underlying autoimmune diseases. CONCLUSIONS We identified several potential additional risk factors for APS clinical manifestations among a large cohort of Chinese aPL carriers. Our data may help physicians to risk stratify aPL-positive Asian patients.
Antibodies, Antiphospholipid ; Antiphospholipid Syndrome/complications* ; Autoimmune Diseases ; Cell-Free Nucleic Acids ; Cohort Studies ; Cross-Sectional Studies ; Female ; Humans ; Morbidity ; Pregnancy ; Risk Factors ; Thrombosis/etiology*