Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP2PP3
The NM_001376.5(DYNC1H1):c.11942C>T(p.Thr3981Ile) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000000684 in 1,461,728 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T3981R) has been classified as Likely benign.
DYNC1H1 (HGNC:2961): (dynein cytoplasmic 1 heavy chain 1) Dyneins are a group of microtubule-activated ATPases that function as molecular motors. They are divided into two subgroups of axonemal and cytoplasmic dyneins. The cytoplasmic dyneins function in intracellular motility, including retrograde axonal transport, protein sorting, organelle movement, and spindle dynamics. Molecules of conventional cytoplasmic dynein are comprised of 2 heavy chain polypeptides and a number of intermediate and light chains.This gene encodes a member of the cytoplasmic dynein heavy chain family. [provided by RefSeq, Oct 2008]
Verdict is Uncertain_significance. Variant got 4 ACMG points.
PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the DYNC1H1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 122 curated pathogenic missense variants (we use a threshold of 10). The gene has 287 curated benign missense variants. Gene score misZ: 10.967 (above the threshold of 3.09). Trascript score misZ: 16.053 (above the threshold of 3.09). GenCC associations: The gene is linked to autosomal dominant non-syndromic intellectual disability, neuronopathy, distal hereditary motor, intellectual disability, autosomal dominant 13, autosomal dominant childhood-onset proximal spinal muscular atrophy without contractures, Charcot-Marie-Tooth disease axonal type 2O.
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.