[Clinical phenotype and genetic analysis of a Chinese pedigree affected with familial progressive hyperpigmentation and hypopigmentation].

OBJECTIVE
To explore the clinical phenotype and genetic basis for a Chinese pedigree affected with familial progressive hyperpigmentation and hypopigmentation (FPHH).


METHODS
Clinical data and family history for a child with FPHH were collected. Peripheral blood samples were collected from the child, his parents and two sisters. Following the extraction of DNA, high-throughput sequencing was carried out to screen for genetic variant associated with the disease. Candidate variant was verified by Sanger sequencing of his family members.


RESULTS
The main clinical features of the proband have included progressive hyperpigmentation and hypopigmentation. High-throughput sequencing revealed that he has harbored a heterozygous c.105T>A (p.Asn35Lys) variant of the KITLG gene, which was unreported previously. Sanger sequencing confirmed that the variant has co-segregated with the disease phenotype in his pedigree.


CONCLUSION
For infants with progressive skin pigmentation and hypopigmentation spots, FPHH should be suspected. The heterozygous c.105T>A (p.Asn35Lys) variant of the KITLG gene probably underlay the FPHH in this pedigree.