Table 1.

Molecular Genetic Testing Used in APOB-Related Familial Hypobetalipoproteinemia

Gene 1MethodProportion of Pathogenic Variants 2 Detectable by Method
APOB Sequence analysis 3>95% 4
Gene-targeted deletion/duplication analysis 5<5% 6
1.

See Table A. Genes and Databases for chromosome locus and protein.

2.

See Molecular Genetics for information on variants detected in this gene.

3.

Sequence analysis detects variants that are benign, likely benign, of uncertain significance, likely pathogenic, or 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.

4.
5.

Gene-targeted deletion/duplication analysis detects intragenic deletions or duplications. Methods used may include a range of techniques such as quantitative PCR, long-range PCR, multiplex ligation-dependent probe amplification (MLPA), and a gene-targeted microarray designed to detect single-exon deletions or duplications.

6.

Large deletions/duplications are very rare [Huang et al 1989].

From: APOB-Related Familial Hypobetalipoproteinemia

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