RESUMO
Compound heterozygous mutations, where two distinct mutated alleles are present within a particular gene, can give rise to the Bardet-Biedl syndrome (BBS). There is limited evidence suggesting that some compound heterozygotes can present with milder phenotypic characteristics than homozygotes. We report on the clinical characteristics of a 22-year-old Puerto Rican male who was compound heterozygous for the Bardet-Biedl syndrome type 1. Our patient had deteriorating visual acuity since early childhood. Clinical and ophthalmic examination revealed retinal dystrophy, polydactyly, and very mild learning disabilities. No additional systemic complications commonly observed in patients with the BBS were present. Allele-specific testing and DNA sequencing revealed compound heterozygous mutations (M390R and E549X) in the BBS1 gene. Our findings could suggest that patients who are compound heterozygotes for these specific BBS mutations can exhibit milder clinical signs than homozygous patients.
Assuntos
Síndrome de Bardet-Biedl/genética , Síndrome de Bardet-Biedl/diagnóstico , Análise Mutacional de DNA , Humanos , Masculino , Proteínas Associadas aos Microtúbulos/genética , Mutação , Adulto JovemRESUMO
OBJECTIVE: To assess the influence of diabetic neuropathy (DN) on balance and functional strength in patients with diabetes mellitus type 2 (DM2). DESIGN: Cross-sectional study. SETTING: Diabetes outpatient unit. PARTICIPANTS: Adults (N=62; age range, 40-65y): 32 with DM2 (19 subjects without DN and 13 with DN) and 30 without DM2 (control group). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Upright balance, evaluated in 4 situations (fixed platform, unstable platform, with eyes open, with eyes closed), and functional strength, assessed with a five-times-sit-to-stand test, were analyzed using an electromagnetic system, with a sensor placed over C7 to allow maximum trunk displacements in the anterior-posterior and medial-lateral directions. The Berg Balance Scale and the Timed Up & Go test were also used. RESULTS: Subjects with DM2 had greater anterior-posterior displacement (P<.05) in the unstable platform with eyes closed condition compared with those without DM2, whereas no difference in medial-lateral displacement was observed between these groups. A difference in time was observed in the five-times-sit-to-stand test (P<.05), with subjects in the control group performing the tasks faster than either group of subjects with DM2. Additionally, subjects in the control group showed a higher score in the Berg Balance Scale and performed the Timed Up & Go test in less time compared with subjects in other groups. CONCLUSIONS: Subjects with DM2, with or without DN, showed deficits in postural control and functional strength compared with healthy individuals of the same age group.