ClinVar Miner

Submissions for variant NM_000104.3(CYP1B1):c.1103G>A (p.Arg368His) (rs79204362)

Minimum review status: Collection method:
Minimum conflict level:
ClinVar version:
Total submissions: 9
Download table as spreadsheet
Submitter RCV SCV Clinical significance Condition Last evaluated Review status Method Comment
Department of Genetics,Sultan Qaboos University Hospital, Oman RCV000023146 SCV000891496 uncertain significance Glaucoma 3, primary congenital, A 2017-12-30 no assertion criteria provided curation
EGL Genetic Diagnostics,Eurofins Clinical Diagnostics RCV000489962 SCV000228774 pathogenic not provided 2015-02-25 criteria provided, single submitter clinical testing
Eye Genetics Research Group,Children's Medical Research Institute RCV000059335 SCV000087421 uncertain significance Congenital ocular coloboma 2012-03-30 no assertion criteria provided research
GeneDx RCV000489962 SCV000577511 uncertain significance not provided 2018-11-30 criteria provided, single submitter clinical testing The R368H variant has been published in association with primary congenital glaucoma (Pasutto et al., 2010; Bejjani et al., 2000). The R368H variant has also been reported in healthy controls and in an unaffected homozygote who had three affected homozygous siblings (Lopez-Garrido et al., 2010; Bejjani et al., 2000). Missense variants in the same residue (R368C, R368L) have been reported in the homozygous and heterozygous states in association with primary congenital glaucoma (Chitsazian et al., 2007; Chen et al., 2008). The R368H variant is observed in 460/16278 (2.9%) alleles from individuals of South Asian background, including 10 homozygous individuals, in the ExAC dataset (Lek et al., 2016). The R368H variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. This substitution occurs at a position that is conserved across species. In vitro functional studies demonstrated that the R368H variant results in a loss-of-function in comparison to wild-type protein (Choudhary et al., 2008; Mookherjee et al., 2012). While in vitro functional studies clearly demonstrate a loss of function and this variant has been identified in many affected individuals, it is clearly not resulting in a disease phenotype in all individuals who harbor this variant. It would seem that the R368H variant either has reduced penetrance in certain individuals or there are other shared variants among affected individuals that results in the disease phenotype. Therefore this variant is considered to be of uncertain significance.
GenomeConnect, ClinGen RCV000709869 SCV000840205 not provided Glaucoma 3, primary congenital, A; Irido-corneo-trabecular dysgenesis no assertion provided phenotyping only GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical significance of the variant.
Illumina Clinical Services Laboratory,Illumina RCV000778148 SCV000914279 pathogenic CYP1B1-Related Disorders 2019-04-05 criteria provided, single submitter clinical testing Across a selection of the available literature, the CYP1B1 c.1103G>A (p.Arg368His) missense variant has been reported in a total of 78 individuals with a spectrum of eye disorders. Within this group, the p.Arg368His variant was identified in a homozygous state in 31 individuals, in a compound heterozygous state in 17 individuals, and in a heterozygous state in 30 individuals. Primary congenital glaucoma was the most commonly described phenotype, however other forms of childhood-onset and adulthood-onset glaucoma, as well as Peter's anomaly, Rieger's anomaly, and a case of micropthalmia with iris and fundal colobomas were also reported (Bejjani et al. 2000; Panicker et al. 2002; Vincent et al. 2002; Reddy et al. 2003; Acharya et al. 2006; Chavarria-Soley et al. 2006; Vincent et al. 2006; Chitsazian et al. 2007; Dimasi et al. 2007; Kumar et al. 2007; Suri et al. 2009; Tanwar et al. 2009; Pasutto et al. 2010; Azmanov et al. 2011; Prokudin et al. 2014). The p.Arg368His variant was also found in a homozygous state in two unaffected individuals and in a compound heterozygous state in ten self-reported unaffected individuals (Bejjani et al. 2000; Suri et al. 2009). The p.Arg368His variant was reported in a heterozygous state in five of 1030 controls and is also reported at a frequency of 0.030660 in the South Asian population of the Exome Aggregation Consortium. This database also includes thirteen homozygotes. In vitro functional studies showed that the variant demonstrated reduced enzymatic activity (Pasutto et al. 2010; Mookherjee et al. 2012). Expression of the variant protein in E. coli resulted in approximately one-sixth of the amount of stable protein compared to wild type and severely reduced metabolism of all substrates tested (Choudhary et al. 2008). While the p.Arg368His variant shows a strong association with disease, the presence of the variant in unaffected individuals in a homozygous and compound heterozygous state, and the high frequency in the population database suggests the variant results in greatly reduced disease penetrance. However, based on the high number of patient cases and functional data, the p.Arg368His variant is classified as pathogenic for CYP1B1-related disorders. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population.
Laboratory for Molecular Medicine,Partners HealthCare Personalized Medicine RCV000844695 SCV000221184 uncertain significance not specified 2018-10-12 criteria provided, single submitter clinical testing Variant classified as Uncertain Significance - Favor Benign. The p.Arg368His var iant in CYP1B1 has been reported in the homozygous or compound heterozygous stat e in several individuals of varying ethnic backgrounds with primary congenital g laucoma (Bejjani 2000, Reddy 2003, Chitsazian 2007, de Melo 2015, Rauf 2016, Yan g 2017) and functional studies suggest an impact to enzyme function (Choudhary 2 008, Pasutto 2010, Mookherjee 2012, Kabra 2017). However, this variant has also been identified in the homozygous or compound heterozygous state in at least 8 unaffected individuals (Bejjani 2000, Alsaif 2018) and has been identified in 3. 1% (939/30622) of South Asian chromosomes, 2.2% (222/10030) of Ashkenazi Jewish chromosomes, and 13 homozygotes in the Genome Aggregation Database (gnomAD, http ://gnomad.broadinstitute.org). It was also identified at an allele frequency of 1.6% in a Saudi Arabian population cohort and 2.4% in a Qatari population cohort (Alsaif 2018, Fakhro 2016). These allele frequencies are higher than the maximu m expected allele frequency for a pathogenic variant in the CYP1B1 gene. In summ ary, the clinical significance of the p.Arg368His variant is uncertain due to co nflicting evidence. ACMG/AMP criteria applied: PM3_VeryStrong, PS3_Moderate, PP3 , BA1, BS2.
OMIM RCV000008178 SCV000028383 pathogenic Glaucoma, early-onset, digenic 2011-03-01 no assertion criteria provided literature only
OMIM RCV000023146 SCV000044437 pathogenic Glaucoma 3, primary congenital, A 2011-03-01 no assertion criteria provided literature only

The information on this website is not intended for direct diagnostic use or medical decision-making without review by a genetics professional. Individuals should not change their health behavior solely on the basis of information contained on this website. Neither the University of Utah nor the National Institutes of Health independently verfies the submitted information. If you have questions about the information contained on this website, please see a health care professional.