Dataset Information

CYP1B1, MYOC, and LTBP2 mutations in primary congenital glaucoma patients in the United States.

ABSTRACT:

Purpose

To screen primary congenital glaucoma patients in the United States for sequence variants within the CYP1B1, LTBP2, and MYOC genes using Sanger and whole exome sequencing.

Design

Retrospective case-control study.

Methods

Fifty-seven primary congenital glaucoma patients (47 families), 71 unaffected family members of the primary congenital glaucoma probands, and 101 healthy unrelated individuals were recruited from a single institution. Sanger sequencing of the primary congenital glaucoma gene, CYP1B1, was performed on 47 proband deoxyribonucleic acid samples. Simultaneously, whole exome sequencing was conducted on 3 families, each including more than 1 affected individual. Concurrently, 33 of 47 primary congenital glaucoma probands with extended family deoxyribonucleic acid samples were screened for LTBP2 and MYOC gene mutations. Exome-sequenced variations were validated by additional Sanger sequencing to confirm segregation of filtered disease-causing single nucleotide variations.

Results

Seven primary congenital glaucoma families (14.9%) manifested disease phenotypes attributable to CYP1B1 mutations. One primary congenital glaucoma family possessed homozygous mutant alleles, whereas 6 families carried compound heterozygous mutations. Five novel combinations of compound heterozygous mutations were identified, of which 2 combinations were found with whole exome sequencing. No disease-causing mutations within the LTBP2 and MYOC genes were discovered.

Conclusions

This study analyzed CYP1B1, LTBP2, and MYOC mutations in a cohort of primary congenital glaucoma patients from the United States, applying whole exome sequencing as a complementary tool to Sanger sequencing. Whole exome sequencing, coupled with Sanger sequencing, may identify novel genes in primary congenital glaucoma patients who have no mutations in known primary congenital glaucoma genes.

SUBMITTER: Lim SH

PROVIDER: S-EPMC3736560 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

CYP1B1, MYOC, and LTBP2 mutations in primary congenital glaucoma patients in the United States.

Lim Sing-Hui SH Tran-Viet Khanh-Nhat KN Yanovitch Tammy L TL Freedman Sharon F SF Klemm Thomas T Call Whitney W Powell Caldwell C Ravichandran Ajay A Metlapally Ravikanth R Nading Erica B EB Rozen Steve S Young Terri L TL

American journal of ophthalmology 20121204 3

<h4>Purpose</h4>To screen primary congenital glaucoma patients in the United States for sequence variants within the CYP1B1, LTBP2, and MYOC genes using Sanger and whole exome sequencing.<h4>Design</h4>Retrospective case-control study.<h4>Methods</h4>Fifty-seven primary congenital glaucoma patients (47 families), 71 unaffected family members of the primary congenital glaucoma probands, and 101 healthy unrelated individuals were recruited from a single institution. Sanger sequencing of the primar ...[more]

PMID: 23218701

Similar Datasets

Project description:Primary congenital glaucoma (PCG) is the most common type of infantile glaucoma, yet it remains a relatively rare disease, because the disease is often transmitted in an autosomal recessive pattern. However, PCG occurs up to 10 times more frequently in certain ethnic and geographical groups where consanguineous relationships are common. The aim of this study was to investigate the distribution of mutations in the cytochrome P450 1B1 gene ( CYP1B1 ) in patients with PCG among different populations around the world from 2011 until May 2016. We referred to the electronic databases, such as Medline, Clinicalkey, Scopus, and ScienceDirect, to search for articles that were published in this area. Nineteen records were included in this qualitative synthesis. CYP1B1 mutations were assessed in 1,220 patients with PCG and identified in 41.6% of them. According to these studies, 99 mutations including 60 novel mutations were found. Nonsignificant difference in the sex ratio has been reported. This current review shows that consanguinity plays an important role in the PCG pathogenesis and transmission; however, sporadic mutations have been found in some cases. A difference in penetrance was highlighted by some mutations. The CYP1B1 mutations were mostly found in the Middle East and the Maghreb with a rate of 64.8 and 54.4%, respectively, followed by Europe (34.7%), Asia (21.3%), and finally the United States (14.9%). Founder mutations in different geographical areas have been discovered. For instance, the p.Gly61Glu, p.Arg390His, p.Gly61Glu, c.4,339delG, p.E387Lys, and p.Val320Leu were considered founder mutations for Iran/Saudi Arabia, Pakistan, Lebanon, Morocco, Europe, and Vietnam/South Korea, respectively. Many common mutations in different countries were found, such as in Morocco, where its mutations were similar to seven other countries. These findings suggest that the ethnic differences and the geographical distribution of PCG give us a large CYP1B1 mutation pattern. Genetic tests looking for founder and common mutations should be the first step in genetic screening for patients with PCG.

Project description:BackgroundCYP1B1 is the most commonly mutated gene in primary congenital glaucoma (PCG). This study was undertaken to identify mutations in CYP1B1 in the Western region of Saudi Arabia.MethodsBlood of patients who had typical findings of PCG, were screened by direct sequencing of all coding exons and splice junctions of the CYP1B1 gene.Results34 patients were studied; 18 patients belonged to 8 families, and 16 patients were non-familial, isolated PCG. Consanguinity was found in 27/34 (79.4%) of cases. All patients were diagnosed to have bilateral PCG at birth except one child, who had glaucoma in the right eye. More males (61.8%) were affected than females (38.2%). 79.4% (27/34) of patients were solved with pathogenic mutations and 20.6% (7/34) remained unsolved. Of the solved ones, 22.2% (6/27) of patients carry a pathogenic allele on one allele while the other allele remained yet to be determined. Direct sequencing of exon 2 revealed two pathogenic variants (p.Gly61Glu, p.Glu229Lys). P.Gly61Glu substitution was found both homozygously in 63% (17/27) of cases, and heterozygously in one patient. P.Glu229Lys variant was found heterozygous in 3.7% (1/27) of cases. One pathogenic variant (p.Arg469Trp) was found in exon 3, and is present homozygously in 14.8% (4/27) of cases while four patients have this variant heterozygously. All mutations were reported previously in the Saudi population, except p.Glu229Lys. Severe cases were associated with p.Gly61Glu, and p.Arg469Trp in 50% and 30% of ten patients respectively.ConclusionsThis study confirms that CYP1B1 mutations are the most frequent cause of PCG in the Saudi population, with p.Gly61Glu being the major disease-associated mutation. P.Glu229Lys is a newly discovered mutation in our PCG patients. Patient lacking mutation in CYP1B1 gene seems likely, to have another genetic loci involved in the pathogenesis of the disease, and need further study. Genetic studies of recessive diseases such as PCG is important in consanguineous populations, since it will increase awareness and allows genetic counseling to be offered to patients and their relatives. This will not only reduce the disease to be inherited to future generations, but will also reduce the disease burden in the community.

Project description:Primary congenital glaucoma (PCG) is a severe form of glaucoma that presents early in life. PCG is a clinical and genetic entity that is distinct from juvenile forms of glaucoma. Inheritance is usually autosomal recessive and therefore the disease might be more common in societies where consanguinity is high. We studied the prevalence of cytochrome P450, family 1, subfamily B, polypeptide 1 (CYP1B1) and latent-transforming growth factor beta-binding protein 2 (LTBP2) mutations in a group of Saudi PCG patients and attempted to correlate the mutation status with the disease severity.Genomic DNA was collected from 54 unrelated Saudi PCG families (74 patients) who were diagnosed as having PCG by standard ophthalmological examinations and screened for mutations in CYP1B1 and LTBP2 by sequencing. We also examined the effect of mutations on the phenotype of patients with PCG (phenotype-genotype correlation).Mutations in CYP1B1 were identified in 41 (75.9%) of affected patients. No mutation in CYP1B1 was found in 13 (24.1%) affected persons. We detected a total of 13 mutations: 9 missense mutations (G61E, A119S, R390H, P437L, D441G, A443G, G466S, G466D, and R469W), 2 deletions (g.4238_4247del and g.7901_7913del), and 2 nonsense mutations (R355X and R444X). Two mutations, G466S and D441G, were novel. The G61E mutation was by far the most common mutation detected. PCG cases with CYP1B1 mutation(s) presented with a high degree of haze and greater cup/disc ratio than those with no mutation(s). Also, PCG cases with a mutation had higher post operative indices in terms of post operative haze and the need for anti-glaucoma medications. Additionally, the surgical success rate was higher 13/14 (92.9%) among cases without mutation than those with mutation 42/60 (70%). No mutation(s) were found in LTBP2 in any of the tested patients.CYP1B1 mutations are the predominant cause of PCG in the Saudi Arabian population with G61E as the dominant disease-associated allele. PCG cases with a mutation had higher last postoperative visit indices in terms of postoperative haze and the need for anti-glaucoma medications. This will be a valuable parameter in predicting disease severity earlier on and might help in predicting the surgical outcome.

Dataset Information

CYP1B1, MYOC, and LTBP2 mutations in primary congenital glaucoma patients in the United States.

Purpose

Design

Methods

Results

Conclusions

Publications

CYP1B1, MYOC, and LTBP2 mutations in primary congenital glaucoma patients in the United States.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets