Parathyroid and thyroid diseases are perhaps a more common cause of cramping in the hands and arms compared with other causes of cramping.

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In this they resemble the three groups of coronaviruses already known to cause animal and human diseases, among them the common cold.

ECONOMIST: SARS: Getting a grippe | The

Any way of systematising knowledge about them would thus be welcome, starting with features that the genes which cause diseases have in common.

ECONOMIST: Genetic disease and evolution

Novel coronavirus is part of a family called coronaviruses, which cause illnesses ranging from the common cold to SARS, or Severe Acute Respiratory Syndrome, as well as a variety of animal diseases.

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