Migraine Without Aura and Migraine with Aura are Inherited Disorders

Abstract

The familial occurrence and mode of inheritance were analysed in families with migraine without aura (MO) and migraine with aura (MA). The probands were found among 4000 persons from the general population. All persons with MA were included as probands, and an equivalent number of probands with MO was selected as a random sample among those with MO. Spouses and first-degree relatives were blindly interviewed. All interviews were performed by one neurological research fellow. The distinct familial patterns indicate that MO and MA have a different aetiology. Compared with the general population, the first-degree relatives of probands with MO had a 1.9-fold increased risk of MO while spouses had a 1.5-fold increased risk of MO, indicating that both genetic and environmental factors are important in MO. The first-degree relatives of probands with MA had a four-fold increased risk of MA while spouses had no increased risk of MA, indicating that MA is determined largely by genetic factors. The complex segregation analysis indicated that both MO and MA have multifactorial inheritance without generational difference.

Migraine comorbidity: from genotype to phenotype

“…Hence, we can expect variability and some degree of overlap in the migraine phenotypes (the clinical manifestation of the genetic defect). Given the complexity of clinical expression and multifactorial etiology [8], family and epidemiologic studies have been confused by gender-dependent, agerelated, and variable penetrance, environmental factors, lack of definition of the migraine syndromes, and referral bias [9]. Furthermore, the diagnosis of migraine and other headache disorders relies almost entirely on the clinical history with no definitive clinical signs or markers of disease being available, especially interictally [10,11].…”

The genetics of migraine

“…A very high percentage, 85%, of first-degree relatives affected with migraine was found by D'Amico et al [4]. In two studies of the disease risk in relatives of migraine probands, Russell et al [5,6] calculated that the risk for first-degree relatives was 3-fold greater in probands with migraine without aura, and 2-fold greater for probands with migraine with aura. These authors went on to study the comparative risk of migraine in spouses versus relatives of migraine sufferers, who share a similar environment but have presumably distinct genotypic backgrounds.…”

Does Early Life Exposure to Cigarette Smoke Permanently Harm Childhood Welfare? Evidence from Cigarette Tax Hikes

“…In online Appendix Table A A remaining concern is that the decision to quit smoking during pregnancy is persistent, and my results are driven by accumulated secondhand exposure throughout childhood. To address this, I show that relative to the current tax, the in utero tax has a much smaller and not significant effect on current smoking (see online Appendix 24 This is a valid placebo variable since the vast majority of chronic headaches in children are migraines ( Abu-Arefeh and Russell 1994), and genetic factors play a leading role in determining the incidence of migraines (Russell, Iselius, and Olesen 1996). 25 My construction of the placebo index follows the process used in Kling, Liebman, and Katz (2007).…”