TABLE 1.

Clinical features of seven new affected individuals from six families with biallelic variants in PIGQ, and review of the literature

Subject ID/source	St1	St2	St3a	St3b	St4	St5	St6
Variants & Inheritance (NM_148920.2)	Homozygous: c.1611del p.R538Afs*24	Maternal: c.1199_1201del p.Y400del Paternal: c.942+1G>A IVS4+1G>A	Maternal: c.1578_1579del p.Q527Afs*75 Paternal: c.1199_1201del p.Y400del	Maternal: c.1578_1579del p.Q527Afs*75 Paternal: c.1199_1201del p.Y400del	Maternal: c.1130_1168del p.A377_S389del Paternal: c.1345G>C p.G449R	Maternal: c.49G>A p.G17R Paternal: c.942+1G>A IVS4+1G>A	Homozygous: c.1670del p.G557Dfs*4
Gender	Female	Female	Female	Female	Female	Male	Male
Ancestry	Turkish	European/Puerto Rican	British Isles/French Canadian	British Isles/French Canadian	Lebanese/Iraqi	Mexican	Afghani
Current age	11 y	6 y 6 mo	Deceased 2 d	Deceased 5 y	Deceased 9 m	2 y 2 m	Deceased 3 y 9 m
Prenatal issues	−	Polyhydramnios	Prominent kidneys, premature rupture of membranes	−	Polyhydramnios, hepatomegaly, hydronephrosis	Dandy Walker malformation	−
Neonatal complications	−	Respiratory distress, hypoglycemia, failed newborn hearing screen in left ear.	Respiratory distress, renal and cardiac failure	Jaundice, secundum atrial ventricular defect detected after birth	Respiratory distress	Respiratory distress, feeding difficulties, jaundice, PDA, PFO	Feeding difficulties, hypertonia
Developmental delay	+	+	N/A	+	+	+	+
Seizure onset	6 mo	7 mo	N/A	Almost 4 mo	7 mo	6 mo	2.5 mo
Hypotonia	+	+	N/A	+	+	+	+
Abnormal movements	+	+	N/A	+	+	+	+
Facial dysmorphism	−	+	+	+	+	+	+
Cranial shape anomalies	−	+	−	−	+	+	+
Teeth anomalies	−	+	N/A	+	Too young	+	−
Skeletal anomalies	+	+	−	+	+	+	−
Joint contractures	+	−	−	+	+	−	−
Other dysmorphic features	+	−	+	−	+	−	−
Deafness	−	−	−	−	Mild left conductive	−	−
Ophthalmological anomalies	+	+	N/A	+	+	+	+.
Cardiac anomalies	−	+	+	+	+	+	+.
Genitourinary abnormalities	+	+	+	No U/S done	+	+	+
Gastrointestinal issues	+	+	N/A	+	+	+	+
Serum alkaline phosphatase	Normal	Intermittently elevated	Not measured	Elevated	Elevated	Not measured	Normal

Subject ID/source	Martin et al 13	Alazami et al 14	Starr et al 15
Variants & Inheritance (NM_148920.2)	Homozygous: c.690‐2A>G	Homozygous: c.619C>T p.R207*	Maternal: c.968_969del p.L323Pfs*119 Paternal: c.1199_1201del p.Y400del
Gender	Male	N/A	Male
Ancestry	West African	N/A	N/A
Current age	Deceased 2 y 4 m	N/A	Deceased 10 mo
Prenatal issues	−	N/A	Severe polyhydramnios requiring multiple amniocentesis fluid reduction procedures
Neonatal complications	At 4 wk: cyanotic episodes with eye twitching, brief stiffening of upper body.	N/A	Feeding difficulties, trembling episodes
DD/ID	+	+	+
Seizure onset	4 wk	N/A	7 mo
Hypotonia	+	N/A	+
Abnormal movements	+	N/A	+
Facial dysmorphism	+	N/A	+
Cranial shape anomalies	−	N/A	+
Teeth anomalies	−	N/A	−
Skeletal anomalies	−	N/A	+
Joint contractures	−	N/A	N/A
Other dysmorphic features	+	N/A	+
Deafness	−	N/A	−
Ophthalmological anomalies	+	+	+
Cardiac anomalies	−	N/A	+
Genitourinary anomalies	−	N/A	+
Gastrointestinal issues	+	N/A	+
Serum alkaline phosphatase	N/A	N/A	Elevated

Note: Further details are provided in Table S2.

Abbreviations: N/A, not applicable; PDA, patent ductus arteriosus; PFO, patent foramen ovale; U/S, ultrasound.