Primary Outcome Measures:
- Use skin assessment techniques to characterize skin properties in male subjects affected by HED compared with healthy controls, including determination of the number of sweat ducts and the rate of sweating [ Time Frame: Day of study conduct ]
Secondary Outcome Measures:
- Collecting demographic and clinical status information in male subjects affected by HED using a medical questionnaire [ Time Frame: Day of study conduct ]
Study Day 1
- Assessment of intrafamilial phenotypic variability in families with multiple HED-affected male siblings [ Time Frame: Day of study conduct ]
Study Day 1 - Comparison of sweat duct counts, sweat rate and hair analysis among HED-affected male siblings
- Evaluation of hair RNA profiles in samples from HED and unaffected male controls [ Time Frame: Day of study conduct ]
Study Day 1 -This is a novel use of the RNASeq technology and will follow the protocol provided by an expert in the field, Dr. Benjamin Yu. The hairs will be cut not plucked from the occipital scalp, with 10-20 collected hairs placed in a regular mailing envelope. The hair-containing envelopes will be shipped to Dr. Yu's laboratory for processing and analysis.
- Confirming the presence of ectodysplasin A (EDA) gene mutations in HED subjects enrolled in this study [ Time Frame: Day of study conduct ]
Study Day 1
This pilot study in affected HED males and unaffected male controls, age 1 year and up, will use minimally invasive devices to image sweat ducts in intact skin, to measure stimulated sweat rate, and in a subset of subjects to collect clipped scalp hair samples for RNA analysis. This study is descriptive in nature and is intended to assess the ability to use innovative approaches to generate data from subjects over a wide age spectrum, with particular emphasis on phenotype variability between male siblings (same mutation). To this end, priority will be given to families that contain multiple affected siblings (i.e. two brothers). Summary data will be generated for the various groups tested, but no power calculations are involved.