A 1927 study supports a current genetic model for inheritance of human scalp hair-whorl orientation and hand-use preference traits.

Study Supports a Current Genetic Model for Inheritance of Human Scalp Hair-Whorl Orientation and Hand-Use Preference Traits

Human handedness and scalp hair-whorl direction develop from a common genetic mechanism.

Theories concerning the cause of right- or left-hand preference in humans vary from purely learned behavior, to solely genetics, to a combination of the two mechanisms. The cause of handedness and its relation to the biologically specified scalp hair-whorl rotation is determined here. The general public, consisting of mostly right-handers (RH), shows counterclockwise whorl rotation infrequently...

Association between scalp hair-whorl direction and hemispheric language dominance.

Asymmetry is a common phenomenon in higher organisms. In humans, the cortical representation of language exhibits a high degree of asymmetry with a prevalence of about 90% of left hemispheric dominance, the underlying mechanisms of which are largely unknown. Another sign that exhibits a form of lateralization is the scalp hair-whorl direction, which is either clockwise or anti-clockwise. The sc...

Orientation of multi-hair follicles in nonbald men: perpendicular versus parallel.

BACKGROUND There has been much debate about the orientation of multi-hair grafts in order to obtain an appearance of fullness after the hair transplantation. OBJECTIVES To analyze natural orientation of multi-hair follicles and the influence of hair flow from the crown swirl. METHODS Natural orientation of follicles was analyzed microscopically in 100 nonbald men: a clockwise whorl flow gro...

Making waves with hairs.

The skin is like a canvas. Pigment distribution, skin appendages, skin ridges, etc. are arranged on the skin surface. The arrangement may be random but every now and then they form specific patterns. In some occasions, the specific arrangement is important for organism function or message display. In all occasions, these distinct arrays provide us with windows into the fundamental processes of ...