An autosomal dominant form of hereditary hypotrichosis simplex maps to 18p11.32–p11.23 in an Italian family

Abstract

We report on a three-generation Italian family with dominant transmission of a form of hereditary hypotrichosis simplex (HHS). The nine affected adults presented with sparse, thin and short hair. Somewhat less sparse and longer hair was observed in the two affected young children in the third generation. Reduced hair growth affected the scalp and body, although normal eyelashes, eyebrows and growth of men's beards were observed. No associated abnormality was detected and the overall psychomotor development of the affected individuals was normal. A phenotypic variation was observed amongst the family members and is suggestive of a reduced penetrance of the trait or the effect of a modifying factor. After exclusion, in our family, of linkage to loci previously described in other forms of atrichia or hypotrichosis, we performed a genome-wide linkage analysis, which resulted in a positive lod score at 18p11.32-p11.23. We defined a critical region of about 35 cM flanked by markers D18S853 and D18S40. The highest two-point lod score was obtained with the microsatellite markers D18S1376, D18S53 and D18S453 (lod score of 3.31 at θ = 0.00). The 18p11.32-p11.23 locus represents the first chromosome region shown to be associated with hereditary hypotrichosis simplex.

Contiguous gene syndrome of holoprosencephaly and hypotrichosis simplex: Association with an 18p11.3 deletion

“…Alopecia universalis with childhood onset also found in our patient is similar to hereditary hypotrichosis simplex (HTS), which maps to18p11.32-p11.23 [Bentley-Phillips and Grace, 1979;Baumer et al, 2000].…”

A locus for hereditary hypotrichosis localized to human chromosome 18q21.1

“…An autosomal dominant form of hypotrichosis simplex (MIM 605389) was localized to chromosome 18p11.32 -p11.23. 11 A form of alopecia, monilethrix (MIM 158000), was localized to chromosome 12q13 and is due to mutations in the hair cortex keratin gene HB1 or HB6. 12 The severity of alopecia is variable from patient to patient and is also variable over time in the same individual.…”

Genetik der monogenen isolierten Alopezien

“…Für die autosomal-dominant vererbte HSG wurden auf Chromosom 18p11 [3] und auf Chromosom 2p25-p23 [17] 2 weitere Genorte berichtet, die verantwortlichen Gene konnten bislang nicht identifiziert werden.…”