Article

Methodology of a multistate study of congenital hearing loss: preliminary data from Utah newborn screening.

Department of Pediatrics, University of Utah, Salt Lake City, 84132, USA.
American Journal of Medical Genetics Part C Seminars in Medical Genetics (impact factor: 4.06). 03/2004; 125C(1):28-34. DOI:10.1002/ajmg.c.30002
Source: PubMed

ABSTRACT A multistate Centers for Disease Control and Prevention (CDC) study was designed to investigate the etiology of congenital hearing loss in infants ascertained through state-mandated hearing screening or early hearing loss detection and intervention (EHDI) programs. At least 50% of permanent childhood-onset hearing loss is due to genetic causes, and approximately 20% of all infants with congenital hearing loss have mutations in the GJB2 gene. Another 1% of childhood hearing loss is due to mitochondrial DNA (mtDNA) mutations. The specific aims of this study are to 1) classify the etiology of congenital hearing loss in infants by doing prospective genetic evaluations of all newborns with permanent hearing loss from defined geographic areas, 2) determine the frequency of mutations in GJB2 and two common mitochondrial mutations in these populations, and 3) establish a model infrastructure linking genetic services to statewide EHDI programs. As of April 2003, Utah is the only center evaluating patients. Study subjects identified through the Utah Department of Health EHDI program are contacted by letter and offered a comprehensive medical genetics evaluation with DNA testing for GJB2 and mitochondrial mutations A1555G and A7445G. To date, 25 probands and their immediate family members have been evaluated. We have identified 20 cases with nonsyndromic hearing loss (7 multiplex and 13 simplex), 4 with syndromic hearing loss, and 1 with presumed cytomegalovirus (CMV)-induced hearing loss. Six of 19 (32%) nonsyndromic cases with sensorineural hearing loss have mutations of one or both alleles of the GJB2 gene, and 21% are homozygous or compound heterozygotes for the 35delG mutation. No A1555G or A7445G mtDNA mutations have been found. Data reported to date include only children born in Utah, but EHDI programs in Hawaii, Rhode Island, and designated areas of Georgia have begun enrolling children in what is now a multistate collaborative study. This is the first comprehensive investigation to determine the etiology of hearing loss from populations ascertained through EHDI programs. The results of this study will facilitate the incorporation of genetic services into EHDI programs.

0 0
 · 
0 Bookmarks
  • Article: Public attitudes regarding the use of residual newborn screening specimens for research.
    [show abstract] [hide abstract]
    ABSTRACT: Many state newborn screening (NBS) programs retain residual NBS bloodspots after the completion of screening. Potential uses for residual specimens include laboratory quality assurance, biomedical research, and, rarely, forensic applications. Our objective was to evaluate public opinion about the policies and practices relevant to the retention and use of residual bloodspots for biomedical research. A total of 3855 respondents were recruited using 3 methods: focus groups (n = 157), paper or telephone surveys (n = 1418), and a Knowledge Networks panel (n = 2280). Some participants (n = 1769) viewed a 22-minute movie about the retention and use of residual specimens while other participants were provided only written information about this practice. All participants were surveyed using a 38-item questionnaire. A diverse set of participants was recruited. Respondents were very supportive of NBS in general and accepting of the use of residual bloodspots for important research activities. Respondents were evenly divided on the acceptability of NBS without parental permission, but the majority of respondents supported the use of an "opt-in" process for parental permission for residual bloodspot retention and use. Viewing the educational movie was associated with greater support for bloodspot retention and use. Our results show that the general public surveyed here was supportive of NBS and residual sample retention and research use. However, there was a clear preference for an informed permission process for parents regarding these activities. Education about NBS was associated with a higher level of support and may be important to maintain public trust in these important programs.
    PEDIATRICS 02/2012; 129(2):231-8. · 4.47 Impact Factor
  • Article: Screening of the mitochondrial A1555G mutation in patients with sensorineural hearing loss.
    [show abstract] [hide abstract]
    ABSTRACT: The A1555G mitochondrial mutation is the main alteration associated with aminoglycoside-induced deafness. to investigate the prevalence of the A1555G mutation in patients sensorineural hearing loss patients with and without aminoglycosides antibiotic use. a study of 27 cases with deafness as the sample, and 100 neonates with normal hearing as the control group. DNA was extracted from blood leukocyte samples, and specific oligonucleotide primers were designed to amplify the cytochrome b gene and the region which encloses the A1555G mutation of the mitocondrial DNA using the polymerase chain reaction and restriction fragment length polymorphism. a cross-sectional case study. a region of the cytochrome b gene was amplified and the presence of the mtDNA was confirmed in all of the 127 cases. The A1555G mutation was not found in any of the 27 patients with hearing loss or the control group with 100 neonates. the results agree with studies stating that the A1555G mutation is not prevalent in the Americas. There is interest in establishing the real prevalence of this mutation and to investigate other mutations that may cause hearing loss, associated or not with the use of aminoglycosides, in the Brazilian population.
    Brazilian journal of otorhinolaryngology 74(5):731-6.

Keywords

35delG mutation
 
7 multiplex
 
A7445G mtDNA mutations
 
childhood hearing loss
 
CMV)-induced hearing loss
 
common mitochondrial mutations
 
compound heterozygotes
 
congenital hearing loss
 
DNA testing
 
GJB2 gene
 
mitochondrial mutations A1555G
 
multistate Centers
 
multistate collaborative study
 
nonsyndromic hearing loss
 
permanent childhood-onset hearing loss
 
permanent hearing loss
 
populations ascertained
 
sensorineural hearing loss
 
state-mandated hearing screening
 
syndromic hearing loss