Table 1.

Results of cerebrospinal fluid analysis of biogenic amines and pterins, phenylalanine loading test results, enzyme guanosine triphosphate cyclohydrolase I activity and molecular analyses of the family with DYT5 dystonia

	CSF*				Oral Phe loading test Phe/Tyr ratio			Enzyme activity GTPCH in fibroblasts	Molecular diagnosis Sequencing GCH1
	5-HIAA (nmol/L)	HVA (nmol/ L)	Neopterin (nmol/L)	Biopterin (nmol/L)	1h	2h	4h
Index case	173	318	3	8	6.6**	5.9**	2.2**	0.39 µU/mg	c.235_240delCTG AGC [p.L79_S80del]
Ref. values (child)	87–366	158–596	9–55	10–52	1.6–5.4	0.9–2.8	0.6–1.5	22 % enzyme activity of normal controls
Mother					7.7	8.2	2.8		c.235_240delCTG AGC [p.L79_S80del]
Father					5.1	2.6	1.4		Negative
Ref. values (adult)					2–6.3	1.17– 4.15	0.6– 1.88

CSF = cerebrospinal fluid, Phe = phenylalanine, Tyr = tyrosine, 5-HIAA = 5-hydroxyindoleacetic acid, HVA = homovanilic acid, GTPCH = guanosine triphosphate cyclohydrolase I

^*CSF was collected five days after discontinuation of treatment with levodopa.

^**Described as patient 14 in the reference by López-Laso et al. [11]