Table 1.

Summary of Molecular Genetic Testing Used in Juvenile Hereditary Hemochromatosis (JHH)

Gene 1Proportion of JHH Caused by Mutation of This GeneTest MethodVariants Detected 2Variant Detection Frequency 3
HJV>90%Targeted analysis for pathogenic variantsp.Gly320ValSee footnote 4
Sequence analysis 5 / scanning for pathogenic variants 6Sequence variants>98%
HAMP<10%Sequence analysis 5 / scanning for pathogenic variants 6Sequence variants>98%

See Molecular Genetics for information on allelic variants.


The ability of the test method used to detect a variant that is present in the indicated gene


Most frequently reported pathogenic variant [Papanikolaou et al 2004]; identified in all affected French-Canadian individuals from the Saguenay-Lac-Saint-Jean region [Lanzara et al 2004]


Sequence analysis detects variants that are benign, likely benign, of uncertain significance, likely pathogenic, or pathogenic. Pathogenic variants may include small intragenic deletions/insertions and missense, nonsense, and splice site variants; typically, exon or whole-gene deletions/duplications are not detected. For issues to consider in interpretation of sequence analysis results, click here.


Sequence analysis and scanning of the entire gene for pathogenic variants can have similar detection frequencies; however, detection rates for scanning may vary considerably among laboratories depending on the specific protocol used.

From: Juvenile Hereditary Hemochromatosis

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