Disease: Platelet-type Von-willebrand Disorder (PT-VWD)

Patient: 17 yo, male, adopted

Variant: GP1BA NM_000173.7: c:580C>T p.(P.Leu194Phe), Heterozygous, gain-of-function

Phenotypes: moderate bleeding phenotype, ISTH-BAT bleeding score of 3, recurrent epistaxis, easy bruising, mild thrombocytopenia

Family: Adopted, no other family history mentioned, segregation studies not performed.

Genetic analysis performed: found variant in GP1BA, results obtained by sanger sequencing.

Variant present in gnomAD(rs368111193): low allele frequency, contradictory classifications

Variant is not present in ClinVar, LOVD, or HGMD databases

According to this paper, ACMG guidelines classified this variant as a VUS.

This paper entered it into Clinvar (var ID 1693270)

Disease: platelet-type von Willebrand disease (PT-VWD)

Patient: 14 yo, Male

Variant: GP1BA NM_000173.7:c.389G>A p.(Arg127Gln), Heterozygous, Gain-of-Function (GOF)

Located in LRR5 domain of GP1BA

Family: Mother did not refer any bleeding symptoms (variant absent in mother) Father not available for collection of clinical history or platelet function testing