I've pored over grainy sepia pictures of long-dead relatives in babushkas; black-and-white snapshots of distant cousins in crisp white linen suits,
soldiers in uniform, ladies with beehive hairdos; Polaroids of bell-bottomed teenagers and long-haired hippies,
and not once have I been able to detect even the slightest trace of August's face in their faces. Not a one.
But after August was born, my parents underwent genetic counseling.
They were told that August had what seemed to be a “previously unknown type of mandibulofacial dysostosis
caused by an autosomal recessive mutation in the TCOF1 gene, which is located on chromosome 5,
complicated by a hemifacial microsomia characteristic of OAV spectrum.”
Sometimes these mutations occur during pregnancy. Sometimes they're inherited from one parent carrying the dominant gene.
Sometimes they're caused by the interaction of many genes, possibly in combination with environmental factors.
This is called multifactorial inheritance.
In August's case, the doctors were able to identify one of the “single nucleotide deletion mutations” that made war on his face.
The weird thing is, though you'd never know it from looking at them: both my parents carry that mutant gene. And I carry it, too.
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