Patient 1 (M)	Patient 2 (M)	Patient 3 (F)	Patient 4 (F)	Patient 5 (F)	Patient 6 (M)
Variants Found	FOXN1 c. 1445_1449delinsCCA; p.R482PfsX46	Brother of Patient 1 with presumed FOXN1 mutation.	FOXN1 c.79C>T; p.L27F Another gene being investigated (VUS)	FOXN1 c.950A>C; p.N317T. Additional single VUS in LYST, STX11, and TMC8, TREX1.	FOXN1 c.965A>G; p.N322S Additional single VUS in DOCK8, IL10RA.	FOXN1 c.1315delC; p. L439CfsX11 DCLRE1C c. 536G>A; p.R179Q
FOXN1 variant prediction	Pathogenic	Under genetic evaluation		VUS	VUS	VUS
Parental Carrier of FOXN1(current age)	Mother, presumed due to phenotype		Father (35)	Unknown carrier	Unknown carrier	Mother (29)
Family History and Phenotype	Maternal thyroiditis; sparse hair, absent eyebrows and brittle, tented nails. Multiple maternal relatives and brother with similar features.		Autoimmune hyperthyroidism. Normal adult WBC, ANC, and T cells at evaluation.	No significant medical history in mother; paternal history is unknown and unavailable.	No significant medical history in mother or father.	Maternal unverified frequent childhood infections and low blood counts; normal adult WBC, ANC, and T cells.
Ancestry	Hispanic (Mexican)		Asian (Chinese)	Asian (Southeast Asian)	Caucasian	Hispanic (Mexican)
Patient Clinical Phenotype	Lymphopenia; sparse, brittle hair, toenail dystrophy	Lymphopenia	Lymphopenia, neutropenia responsive to GCSF, growth failure, abnormal facies, delayed speech	Lymphopenia	Lymphopenia, asymptomatic transaminitis	Lymphopenia, neutropenia responsive to GCSF
NBS TRECs (normal >18 copies/uL)	1	9	Undetectable	10	12	Undetectable
CBC (at referral)
WBC (K/uL)	5.2	5.2	5.3	7.9	4.0	6.9
ANC (cells/uL)	2200	1700	2279	3100	1200	2600
ALC (cells/uL)	1200	2000	1500	2400	2100	1300
Lymphocyte Subsets (at referral)
CD3	432	759	600	1224	1007	78
CD3+CD4+	276	506	330	792	782	65
CD3+CD8+	158	239	256	408	203	<20
CD19+	276	308	75	600	727	364
CD56+	336	730	690	432	362	741
CD4+45+RA	47	341	33	198	551	<20
CD4+45+RO	<20	170	38	208	246	43
CD8+45+RA	117	234	156	65	191	<20
CD8+45+RO	<20	7	18	<20	<20	<20
Immunoglobulins (at referral)
IgG	747	740	710	907	516	1360
IgA	<7	<7	<7	9	8	<7
IgM	23	26	64	72	45	41
Lymphocyte proliferation to PHA	Normal	Normal	Normal	Normal	Normal	Normal, then diminished by 1.5 months of age
Spectratyping	Not done	Not done	Acceptable TCR Vb diversity for age	Not done	Not done	Abnormal, restricted pattern of TCR Vb diversity
Thymus shadow	Unknown	Unknown	Normal	Unknown	Unknown	Diminished
Infections	Urinary tract infection, otitis media	None	Thrush, treated with oral fluconazole only	None	None	None pre HCT*
Treatment	Home isolation, no prophylaxis	Home isolation, no prophylaxis	Home isolation and fungal prophylaxis until ~12 mo; remains on PCP prophylaxis, GCSF	Home isolation, no prophylaxis	Home isolation, no prophylaxis	Hospital isolation. GCSF, paternal haploidentical HCT
Outcome	Alive at 36 months with no major infections	Alive at 7 months with no major infections	Alive at 18 months with no major infections	Alive at 16 months with no major infections	Alive at 10 months with no major infections	Alive >12 months post HCT; delayed T-cell reconstitution, AIHA**
Most recent ALC	1200 cells/uL	2080 cells/uL	1020 cells/uL	5060 cells/uL	2300 cells/uL	On immunosuppression